Retention Knobs

Download the Full Retention Knobs Catalog

Every size, dimension and part number in one printable PDF — plus the coolant-fed tooling lines not shown on this page.

Get the Free PDF →

Retention Knobs & Retention Knob Sockets

CV flange, BT flange and DIN / ISO flange retention knobs in styles A through J, plus retention knob sockets for installation and removal. Each knob is listed with its thread, angle, critical dimensions and matching socket. Special-order knobs are available to your drawing.

  • CV-30 – CV-60
  • BT-30 – BT-50
  • DIN / ISO 40 – 50
  • Styles A – J
  • Retention Knob Sockets
  • Special Orders
Retention Knob Sockets • 1/2″ Drive

Retention Knob Sockets

IMPERIAL

READ CAREFULLY WHEN SELECTING A SOCKET

  • Life time guarantee
  • Made in the USA
  • Saves time
  • Sockets have 1/2” drive
  • Ideal tightness is achieved
▶View All Retention Knob Sockets9 sockets
Part
Number
Maximum
Flat (In.)
Maximum
Torque Ft-Lb
•WRKS300.53540
•WRKS30M0.51140
•WRKS30D0.55640
WRKS400.75585
WRKS40M0.71185
WRKS451.004100
WRKS45M0.950100
WRKS501.255110
WRKS50M1.185110

• Note: WRKS30, WRKS30M and WRKS30D are 3/8” Drive Sockets

Sockets aid in the installation and removal of Retention Knobs. Ideal tightness is achieved, without rounding off the corners of the Retention Knob.

Note: Some Retention Knobs have mixed standards. Check the shoulder and Wrench Sizes carefully when selecting a Socket to fit other Retention Knobs not listed above.

CV Flange Retention Knobs • CV-30 to CV-60

CV Flange Retention Knobs

IMPERIAL

STYLES A – J • CV-30 • CV-40 • CV-45 • CV-50 • CV-60

CAUTION: Retention knobs are manufactured to the specifications of the machine tool builder and any deviation from this could cause serious problems. Retention knobs are not normally interchangeable and failure to use the correct configuration can cause the toolholder to slip from the spindle which can result in serious damage. Retention knob fractures may occur from several factors, some of which are: improper knob configuration, mis-aligned machines, metal fatigue due to use, dropped tools, over torquing etc. Unless parts are ordered to a specific drawing or catalog number, we suggest you furnish a drawing of the part, make model number and serial number of the equipment requiring the knob.

▶View All CV Flange Retention Knobs73 knobs
GW No.DescriptionStyleTAD1D2D3D4LL1L2Socket
CV-30 • TOOL SHANK CV-30
WRK1111130E-A-P / A-45-.320CH0.500-13450.52000.38500.18700.51201.27200.32000.4600WRKS30
CV-40 • TOOL SHANK CV-40
WRK1112240E-A / A-45-.440(C.281)H0.625-11450.74000.49000.28100.63601.62500.44000.6400WRKS40
WRK1112340E-A / A-45-.440H0.625-11450.74000.4900N/A0.63601.62500.44000.6400WRKS40
WRK11314BOSTON DIGITALSPEC0.625-11150.50000.3100N/AN/A1.50000.59300.7500N/A
WRK1262240E-A / PT-45-1.000A0.625-11450.58800.3920N/AN/A2.26501.00001.2650WRKS40M
WRK1712240E-A / PT-45-1.139A0.625-11450.59400.4060N/AN/A2.25001.13901.4380WRKS40M
WRK1712340E-A / PT-45-1.139(C.157)A0.625-11450.59400.40600.1570N/A2.25001.13901.4380WRKS40
WRK3111440E-BT (A) / PT-45-.988C0.625-11450.58900.3920N/A0.63602.25000.98801.2640WRKS40
WRK31114A40E-BT (A) / PT-60-.988C0.625-11600.58900.3920N/A0.63602.25000.98801.2640WRKS40
WRK31114B40E-BT (A) / PT-90-.988C0.625-11900.58900.3920N/A0.63602.25000.98801.2640WRKS40
WRK31114B-P40E-A / PT-90-.988B0.625-11900.58900.3920N/AN/A2.12500.98801.2640WRKS40
WRK3122240E-BT / SP-90-.777D0.625-11900.58900.3880N/A0.62502.03700.77701.0530WRKS40
WRK3122640E (A) / A-45-.440(C.281)H0.625-11450.74000.49000.28100.64051.62400.44000.6400WRKS40
WRK31226-H40E (A) / A-45-.440H0.625-11450.74000.4900N/A0.64051.62400.44000.6400WRKS40
WRK3151440E-BT (A) / PT-45-.988(C.200)C0.625-11450.58900.39200.20000.63602.25000.98801.2640WRKS40
WRK3161440E-A (A) / PT-45-.7066(C.079)A0.625-11450.43100.27400.0790N/A1.88900.70660.9035WRKS40
WRK3161640E-A / I(A)-15-.792I0.625-11150.74600.5490N/A0.64062.00800.79201.0280WRKS40
WRK3161740E-A (A)-O / I(A)-15-.792(C.236)I0.625-11150.74600.54900.23600.64062.00800.79201.0280WRKS40
WRK31814A40E-BT / PT-60-.988(C.138)C0.625-11600.58900.39200.13800.63602.25000.98801.2640WRKS40
WRK3211440E-A /.124 / PT-45-.988C0.625-11450.58800.39200.63600.63602.12500.98801.2640WRKS40
WRK32114A40E-A /.124 / PT-60-.988C0.625-11600.58800.39200.63600.63602.12500.98801.2640WRKS40
WRK32114B40E-A /.124 / PT-90-.988C0.625-11900.58800.39200.63600.63602.12500.98801.2640WRKS40
WRK32114-C40E-A /.124 / PT-45-.988(C.187)C0.625-11450.58800.39200.18700.63602.12400.98801.2640WRKS40
WRK3213040E-A-OP /.124 / PT-45-.988(C.187)-OIDC0.625-11450.58800.39200.18700.64062.12400.98801.2640WRKS40
WRK32414B40E-BT / PT-90-.707C0.625-11900.58900.3920N/A0.63601.97000.70700.9840WRKS40
*WRK3271640E-A-OP / A-45-.440(C.160)J0.625-11450.74000.49000.16000.64061.62400.44000.6400WRKS40
**WRK3275040E-A-OP / A-45-.440(C.160)J0.625-11450.74000.49000.16000.64061.62400.44000.6400WRKS40
WRK3275140E-BT / PT-60-.481H0.625-11600.58800.3920N/A0.64061.73200.48100.7570WRKS40
WRK3291440E-BT (BT) / I(A)-15-.9035(C.281)I0.625-11150.74600.54900.28100.64062.12600.90351.1397WRKS40
WRK3503040E-BT(A) / PT-90-.988(C224)C0.625-11900.58900.39200.22400.64062.25000.98801.2640WRKS40
WRK5102540E-I ( A ) / I(B)-45-.433(C281)H0.625-11450.74000.50400.28100.64061.75790.43890.6456WRKS40
WRK7112340E-A / D(A)-15-.7874(C.236)F0.625-11150.74700.54900.23600.64062.00400.78741.0240WRKS40
WRK7112540E-A / D(A)-15-.7874F0.625-11150.74700.5490N/A0.64062.00400.78741.0240WRKS40
WRK7502240E-A / D(A)-15-.7874(C.236)-OF0.625-11150.74700.54900.23600.64061.88000.78741.0240WRKS40
CV-45 • TOOL SHANK CT-45
WRK1113345E-A / A-45-.580(C.375)H0.750-10450.94000.60500.37500.76101.97200.58000.8200WRKS45
WRK1113545E-A / A-45-.580H0.750-10450.94000.6050N/A0.76101.97200.58000.8200WRKS45
¹WRK1713645E-A / S-90-1.000E0.750-10900.81200.5620N/AN/A2.12001.00001.2000N/A
WRK3111645E-BT / BT-45-1.228C0.750-10450.74600.5490N/A0.76102.77001.22801.5830WRKS45
WRK31116A45E-BT / BT-60-1.228C0.750-10600.74600.5490N/A0.76102.77001.22801.5830WRKS45
WRK31116B45E-BT / BT-90-1.228C0.750-10900.74600.5490N/A0.76102.77001.22801.5830WRKS45
WRK7113445E-A / D(A)-15-.906(C.375)F0.750-10150.90400.66700.37500.76102.17000.90551.1810WRKS45M
WRK7113645E-A / D(A)-15-.906F0.750-10150.90400.6670N/A0.76102.17000.90551.1810WRKS45M
CV-50 • TOOL SHANK CV-50
WRK1114350E-A / A-45-.700(C.500)H1.000-8451.14000.82000.50001.02602.57500.70001.0000WRKS50
WRK1114450E-A / A-45-.700(C.468)H1.000-8451.14000.82000.46801.02602.57500.70001.0000WRKS50
WRK1114650E-A / A-45-.700H1.000-8451.14000.8200N/A1.02602.57500.70001.0000WRKS50
WRK1374450E-A / SP-40-1.025LUCAS1.000-8400.84800.4980N/AN/A2.96001.02501.5500N/A
WRK1714450E-A / A-45-.700(C.468)A1.000-8451.14000.82000.4680N/A2.30000.70001.0000WRKS50M
WRK3111850E-BT / PT-45-1.384C1.000-8450.90300.6680N/A1.02603.35001.38401.7780WRKS50
WRK31118A50E-BT / PT-60-1.384C1.000-8600.90300.6680N/A1.02603.35001.38401.7780WRKS50
WRK31118B50E-BT / PT-90-1.384C1.000-8900.90300.6680N/A1.02603.35001.38401.7780WRKS50
WRK31118B-P50E-A / PT-90-1.384B1.000-8900.90300.6680N/AN/A3.08001.38401.7780WRKS50
WRK31118D50E-A / PT-45-1.384(C.312)C1.000-8450.90300.66800.31201.02603.08001.38401.7780WRKS50
WRK31138A50E-BT / PT-60-1.376C1.000-8600.90300.6680N/A1.02603.35301.37601.7700WRKS50
WRK31244A50E-BT / M2-90-1.384E1.000-8900.90800.6680N/A1.02603.35001.38401.7790WRKSS40
WRK3124650E-BT / A-45-.700(C.390)-OFH1.000-8451.14000.82000.39001.02602.30000.70001.0000WRKS50M
WRK31251A50E-A / A-45-.700(C.390)-OIDH1.000-8451.14000.82000.39001.03032.30300.70001.0000WRKS50M
WRK3164550E-BT / PT-45-1.384(C.390)C1.000-8450.90300.66800.39001.02603.35501.38401.7780WRKS50
WRK3164750E-BT-OP / PT-45-1.384(C.236)C1.000-8450.90300.66800.23601.02603.35501.38401.7780WRKS50
WRK31647H50E-BT-OP / PT-45-1.384(C.236)-OIDC1.000-8450.90300.66800.23601.02603.35501.38401.7780WRKS50
WRK31844A50E-BT / PT-60-1.384(C.335)C1.000-8600.90300.66800.33501.02603.35501.38401.7780WRKS50
WRK3212950E-BT-OP / PT-90-1.384(C.118)-OC1.000-8900.90300.66800.23601.02603.35301.38401.7780WRKS50
WRK32418B50E-A / PT-90-.903B1.000-8900.94200.7060N/AN/A2.51900.90301.2180WRKS50M
WRK32419B50E-A / PT-90-.903(C.250)B1.000-8900.94200.70600.2500N/A2.51900.90301.2180WRKS50M
WRK32420B50E-A / PT-90-.903(C.315)B1.000-8900.94200.70600.3150N/A2.51900.90301.2180WRKS50M
WRK3274950E-A-OP / PT-60-1.384(C.236)C1.000-8600.90300.66800.23601.02323.35301.38401.7780WRKS50
WRK34218B50E-BT / PT-90-1.384(C.250)C1.000-8900.90300.66800.25001.02603.35001.38401.7780WRKS50
WRK51041(86)50E-A / I(A)-15-.9901I1.000-8151.10000.8250N/A1.03012.91100.98221.3365WRKS50
WRK5104750E-A / I(B)-45-.7069(C.468)I1.000-8451.14000.76600.4680N/A2.58390.70691.0049WRKS50
WRK5164450E-A / SP-.141R-1.260SPECIAL1.000-8.141R.0.78500.6310N/AN/A2.86101.26591.5609N/A
WRK5164850E-A / SP-.141R-2.260SPECIAL1.000-8.141R.0.78500.6310N/AN/A3.86102.26592.5609N/A
WRK7114550E-A / D(A)-15-.984(C.468)F1.000-8151.10100.82500.46801.03012.91400.98401.3380WRKS50M
WRK7114750E-A / D(A)-15-.984F1.000-8151.10100.8250N/A1.03012.91400.98401.3380WRKS50M
CV-60 • TOOL SHANK CV-60
WRK1115560E-A / A -45-1.080(C.500)A1.250-7451.46001.04500.5000N/A3.20001.08001.5000N/A

* 8mm Counterbore on inside of thread stud.

** 6mm Counterbore on inside of thread stud.

• ¹ Manufactured without Pilot.

CV Flange Shank Dimensions

TaperABCD
301.2501.8121.8751/2-13
401.7502.5002.6875/8-11
452.2503.2503.2503/4-10
502.7503.8754.0001-8
604.2505.5006.3751 1/4-7
BT Flange Retention Knobs • BT-30 to BT-50

BT Flange Retention Knobs

METRIC

STYLES A – J • BT-30 • BT-35 • BT-40 • BT-45 • BT-50

CAUTION: Retention knobs are manufactured to the specifications of the machine tool builder and any deviation from this could cause serious problems. Retention knobs are not normally interchangeable and failure to use the correct configuration can cause the toolholder to slip from the spindle which can result in serious damage. Retention knob fractures may occur from several factors, some of which are: improper knob configuration, mis-aligned machines, metal fatigue due to use, dropped tools, over torquing etc. Unless parts are ordered to a specific drawing or catalog number, we suggest you furnish a drawing of the part, make model number and serial number of the equipment requiring the knob.

▶View All BT Flange Retention Knobs37 knobs
GW No.DescriptionStyleTAD1D2D3D4LL1L2Socket
BT-30 • TOOL SHANK BT-30
WRK3110930M-BT / PT-45-.707CM12X1.75450.43100.2740N/A0.49181.69000.70700.9040WRKS30M
WRK31109A30M-BT / PT-60-.707CM12X1.75600.43100.2740N/A0.49181.69000.70700.9040WRKS30M
WRK31109B30M-BT / PT-90-.707CM12X1.75900.43100.2740N/A0.49181.69000.70700.9040WRKS30M
WRK31109C30M-BT / PT-45-.707(C.110)CM12X1.75450.43100.27400.11000.49181.69000.70700.9040WRKS30M
WRK3262130M-JIS / P-15-.7224(C.156)CM12X1.75150.47200.31300.15600.49181.69300.72240.9194WRKS30M
BT-35 • TOOL SHANK BT-35
WRK3111135M-BT / PT-45-.884CM12X1.75450.51000.3320N/A0.51141.88700.88401.1000N/A
WRK31111A35M-BT / PT-60-.884CM12X1.75600.51000.3330N/A0.51141.88700.88401.1000N/A
WRK3232835M-BT / PT-45-.634CM12X1.75450.40800.3130N/A0.51111.41700.63400.7870WRKS30D
WRK3261135M-BT / PT-45-.884CM12X1.75450.53800.3480N/A0.51052.09000.88401.1000N/A
WRK3261335M-BT / PT-90-.7067CM12X1.75900.54900.3130N/A0.49181.77000.70670.9040N/A
WRK3261435M-BT / PT-60-.884CM12X1.75600.53800.3480N/A0.49182.08700.88401.1000N/A
BT-40 • TOOL SHANK BT-40
WRK1112640M-BT / A-45-.552HM16X2.00450.74000.4900N/A0.66891.61200.55200.7520WRKS40
WRK11126A40M-BT / A-45-.552(C.281)HM16X2.00450.74000.49000.2810.66891.73600.55200.7520WRKS40
WRK1712640M-BT / PT-45-1.251CM16X2.00450.59200.4040N/A0.66892.53401.25101.5500WRKS40M
WRK1712740M-BT / PT-45-1.251(C.141)CM16X2.00450.59200.40400.1410.66892.53401.25101.5500WRKS40M
WRK3111340M-BT / PT-45-1.100CM16X2.00450.58900.3920N/A0.66902.36001.10001.3760WRKS40
WRK31113A40M-BT / PT-60-1.100CM16X2.00600.58900.3920N/A0.66902.36001.10001.3760WRKSS40
WRK31113B40M-BT / PT-90-1.100CM16X2.00900.58900.3920N/A0.66902.36001.10001.3760WRKS40
WRK31113D40M-BT / PT-45-1.100(C.197)CM16X2.00450.58900.39200.1970.66902.36001.10001.3760WRKS40
WRK31113E40M-BT / PT-60-1.100(C.197)CM16X2.00600.58900.39200.1970.66902.36001.10001.3760WRKS40
WRK31113F40M-BT / PT-90-1.100(C.197)CM16X2.00900.58900.39200.1970.66902.36001.10001.3760WRKS40
WRK3291240M-BT / I(A)-15-.9035IM16X2.00150.74600.5490N/A0.66902.12600.90351.1397WRKS40
WRK3291340M-BT / I(A)-15-.9035(C.281)IM16X2.00150.74600.54900.2810.66902.12600.90351.1397WRKS40
BT-45 • TOOL SHANK BT-45
WRK3111545M-BT / PT-45-1.218CM20X2.50450.74600.5490N/A0.82642.75601.21801.5730WRKS45M
WRK31115A45M-BT / PT-60-1.218CM20X2.50600.74600.5490N/A0.82642.75601.21801.5730WRKS45M
WRK31115B45M-BT / PT-90-1.218CM20X2.50900.74600.5490N/A0.82642.75601.21801.5730WRKS45M
BT-50 • TOOL SHANK BT-50
WRK11144A50M-A / A-45-.700(C.468)HM24X3.00451.14000.82000.46800.98392.58000.70001.0000WRKS50
WRK1114850M-A-P / A-45-.700HM24X3.00451.14000.8200N/A0.98392.58000.70001.0000WRKS50
WRK11148A50M-A-P / A-45-.700(C.468)HM24X3.00451.14000.82000.46800.98392.58000.70001.0000WRKS50
WRK3111750M-BT / PT-45-1.376CM24X3.00450.90300.6680N/A0.98393.35001.37601.7700WRKS50M
WRK31117A50M-BT / PT-60-1.376CM24X3.00600.90300.6680N/A0.98393.35001.37601.7700WRKS50M
WRK31117B50M-BT / PT-90-1.376CM24X3.00900.90300.6680N/A0.98393.35001.37601.7700WRKS50M
WRK31246A50M-A / A-45-.700(C.390)-OFHM24X3.00451.14000.82000.39000.98392.58000.70001.0000WRKS50M
WRK3164350M-BT / PT-45-1.376(C.236)CM24X3.00450.90300.66800.23600.98393.35001.37601.7700WRKS50M
WRK3165250M-I-O / PT-45-1.384(C.236)CM24X3.00450.90300.66800.23600.98393.35801.38401.7780WRKS50M
WRK3184350M-BT / PT-60-1.376(C.312)CM24X3.00600.90300.66800.31200.98393.35001.37601.7700WRKS50M
WRK34217B50M-BT / PT-90-1.376(C.250)CM24X3.00900.90300.66800.25000.98393.35001.37601.7700WRKS50M

BT Flange Shank Dimensions

TaperGage LineA Lg.B Lg.Flange O.D.Thd. Size
301.2501.9850.7871.811M12 X 1.75
351.5002.2990.8662.087M12 X 1.75
401.7502.6540.9842.480M16 x 2.00
452.2503.3781.1813.346M20 x 2.50
502.7504.1261.3783.937M24 x 3.00
DIN / ISO Flange Retention Knobs • Tool Shank 40 to 50

DIN / ISO Flange Retention Knobs

METRIC

STYLES C • F • H • I | TOOL SHANK 40 • 45 • 50

CAUTION: Retention knobs are manufactured to the specifications of the machine tool builder and any deviation from this could cause serious problems. Retention knobs are not normally interchangeable and failure to use the correct configuration can cause the toolholder to slip from the spindle which can result in serious damage. Retention knob fractures may occur from several factors, some of which are: improper knob configuration, mis-aligned machines, metal fatigue due to use, dropped tools, over torquing etc. Unless parts are ordered to a specific drawing or catalog number, we suggest you furnish a drawing of the part, make model number and serial number of the equipment requiring the knob.

▶View All DIN / ISO Flange Retention Knobs15 knobs
GW No.DescriptionStyleTAD1D2D3D4LL1L2Socket
TOOL SHANK 40
WRK11122A40M-BT (I) / A-45-.440(C.281)HM16X2.00450.74000.49000.28100.66891.62400.44000.6400WRKS40
WRK1112540M-A (I) / A-45-.440HM16X2.00450.74000.4900N/A0.66891.62400.44000.6400WRKS40
WRK35000V40M-BT(I) / PT-45-.988CM16X2.00450.58900.3920N/A0.66892.36600.98801.2640WRKS40
WRK3502640M-BT(I) / PT-60-.988CM16X2.00600.58900.3920N/A0.66892.36600.98801.2640WRKS40
WRK3503840M-BT(I) / PT-90-.988CM16X2.00900.58900.3920N/A0.66892.36600.98801.2640WRKS40
WRK5102240M-I (I) / I(A)-15-.787(C.236)IM16X2.00150.74600.54900.23600.66902.12500.78741.0245WRKS40
WRK5102440M-I / I(B)-45-.433HM16X2.00150.74600.5490N/A0.66902.12500.78741.0245WRKS40
WRK5102640M-I (I) / I(A)-15-.787IM16X2.00150.74600.5490N/A0.66902.12500.78741.0245WRKS40
WRK7112240M-D / D(A)-15-.787(C.236)FM16X2.00150.74680.54920.23600.66822.13600.78701.0236WRKS40
WRK7112440M-D / D(A)-15-.787FM16X2.00150.74680.5492N/A0.66802.13600.78701.0236WRKS40
TOOL SHANK 45
WRK5103345M-I / I(A)-15-.906(C.375)IM20X2.50150.90360.66730.37500.82652.55900.90551.1811WRKS45
WRK5103745M-I / I(A)-15-.906IM20X2.50150.90360.6673N/A0.82652.55900.90551.1811WRKS45
TOOL SHANK 50
WRK35048B50M-I / PT-90-1.384CM24X3.00900.90300.6680N/A0.98303.35301.38401.7780WRK50S
WRK7114450M-D / D(A)-15-.984(C.468)FM24X3.00151.10100.82500.46800.98302.92000.98401.3380WRKS50M
WRK7114650M-D / D(A)-15-.984FM24X3.00151.10100.8250N/A0.98302.92000.98401.3380WRKS50M

DIN / ISO Flange Shank Dimensions

TaperABCD
301.2501.9671.876M12 X 1.75
401.7502.5002.687M16 X 2.00
452.2503.2483.250M20 X 2.50
502.7503.8374.000M24 X 3.00
Retention Knobs, Special Orders

Retention Knobs, Special Orders

When ordering retention knobs not shown in the above listings, the following information is required:

  • 1. Machine tool manufacturer
  • 2. Model number and serial number
  • 3. Sample retention knob (if available)
  • 4. Drawing complete with critical dimensions as shown in the sample sketch.

Note: This sketch of a Japanese style knob can be used for reference when requesting quotations of identifying knobs, all dimension shown are critical for proper fit.

Angle types: I – 45° · II – 60° · III – 90° · IV – 75°

Take the Retention Knobs Catalog With You

Get the complete printable PDF — specs, dimensions and every part number — sent straight to your inbox.

Download the PDF →