The 6.1 is used when there is very limited or no access to one of the support bores.

It consists of one pin with tapered ends and a centre hole, one centre axle working together with a nut and conical sleeve on the limited side, one regular conical sleeve working together with an end-plate and fasteners on the reachable side. The truly unique attribute of the 6.1 is the ability to ensure a zero tolerance fit in the limited support bore as well as in the reachable support. This solution only requires space to assemble from one side. A torque wrench is used on one side to apply the correct torque to the assembly.

A bondura® multi tool (BMT) is recommended to disassemble the 6.1.