Let-down keys Bergeon

The let-down keys have an insert-holder and are fitted with a rubber handle. The drum consists of 24 numbered inserts with square pegs from 1.75 to 7.5 mm (No. 000 to 21).

For let down mainspring:

Choose the chuck corresponding to the winding square arbor and fix it to the tool. Put the tool into the square arbor. Exert a firmly pressure on the rubber cylinder. Turn slightly the tool clockwise. Lift up the click with one hand. Let down by progressively releasing grip, so that the rubber cylinder slowly rubs on the tool.

For winding up mainsprings:

Choose the chuck corresponding to the winding square arbor and fix it to the tool provided with the metal handle. Wind up as with a normal key.

BERGEON-No. 2301

Weight: 940 g