Bulle Silver Plated Contact Spring

This 0.15mm wire diameter silver plated copper spring has a 4mm end loop and 2mm diameter coils. The spring is fitted to the Bulle with one end attached to the end of the fork arbor and the other by a small adjustable brass strip. The fork has a small silver groove that the large loop end rolls on with each side to side movement of the pendulum. When attaching, the spring must not be stretched as it will distort very easily. The strip end should be attached first and then the strip adjusted until the loop end just loops over the groove with no stretching.