Precise Retention Knobs Style 1, BT-40 & BT-50
- BT-40 Heat treated alloy steel.
- BT-50 SNCM-21 alloy steel hardened to HRC 52-56º
- All dimensions are in accordance to MAS specifications for BT holders.
- BT-40 thread is M16 X 2.0.
- BT-50 thread is M24 X 3.0
Item No. | 3900-5392 | 3900-5393 | 3900-5503 | 3900-5504 |
Thru Coolant | Yes | Yes | N/A | N/A |
Angle A | 45º | 60º | 45º | 60º |
Knob Dia. D1 | 0.591"/15mm | 0.591"/15mm | 0.591"/15mm | 0.591"/15mm |
Neck Dia. D2 | 0.394"/10mm | 0.394"/10mm | 0.394"/10mm | 0.394"/10mm |
Hole Dia. D3 | 0.150"/3.8mm | 0.150"/3.8mm | N/A | N/A |
Pilot Dia. D4 | 0.669"/17mm | 0.669"/17mm | 0.669"/17mm | 0.669"/17mm |
Diameter D | 0.906"/23mm | 0.906"/23mm | 0.906"/23mm | 0.906"/23mm |
OAL L | 2.374"/60.3mm | 2.374"/60.3mm | 2.374"/60.3mm | 2.374"/60.3mm |
Shoulder L1 | 1.102"/28mm | 1.102"/28mm | 1.102"/28mm | 1.102"/28mm |
Shoulder L2 | 2.421"/61.5mm | 2.421"/61.5mm | 2.421"/61.5mm | 2.421"/61.5mm |
Item No. | 3900-5397 | 3900-5508 |
Thru Coolant | Yes | N/A |
Angle A | 45º | 45º |
Knob Dia. D1 | 0.906"/23mm | 0.906"/23mm |
Neck Dia. D2 | 0.669"/17mm | 0.669"/17mm |
Hole Dia. D3 | 0.268"/6.8mm | 0.268"/6.8mm |
Pilot Dia. D4 | 0.984"/25mm | 0.984"/25mm |
Diameter D | 1.496"/38mm | 1.496"/38mm |
OAL L | 3.346"/85mm | 3.346"/85mm |
Shoulder L1 | 1.378"/35mm | 1.378"/35mm |
Shoulder L2 | 3.937"/100mm | 3.937"/100mm |
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For more info, visit www.p65warnings.ca.gov.
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