Set of 7 long arm spline keys( Bristol keys): S-096-6L, S-111-6L, S-133-6L, S-145-6L, S-168-6L, S-183-6L, S-216-6L The Bristol Spline Drive Developed by Bristol, the multiple spline drive system is recognized by designengineers as the superior method of transmitting torque because nearly 100% ofwrenching force is applied at right angles to the load bearing spline surfaces of thesocket. Other drive systems dissipate a significant amount of force into radial thrust,tending to expand the socket rather than tighten the screw. The substantial and effective wrench engagement inherent in the Bristol designaddresses the problems caused by other fastening systems such as cam-out, socket reaming and "rounding" of wrenches. Decades ago, Bristol engineers invented the Bristol Spline Drive System for use inelectromechanical instruments. They required screws and wrenches that couldstand up to industrial environments, vibrations, and frequent removal and resetting. Bristol wrenches have been in continuous production in the United States since theiroriginal introduction
