The watch straps are usually supported by a "pumps" system which is a metal axis which can retract thanks to its spring system.

To drive a pump, it is recommended to use a "Bergeon" tool that is easily placed between the pump end and the watch case. This space is in the order of some micro millimetres. The fork of the "Bergeon" tool is designed to fit in this location. Simply operate a perpendicular pressure once the tool is placed and the strap can be removed.

Some case lugs are pierced, then you have to use the other part of the "Bergeon" tool which is composed of a tip and put it in the hole to make action and remove the bracelet.

To replace the strap, the pump must be put back into the Centre of the bracelet. The holes in the housing fasteners on the lugs must then be picked up. With a lever effect, the pumps come to fit in the holes. You should hear a "click" when they are properly housed.

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