Kryos MechaQuartz Chronograph, Cal. 631
Watch is easy to open
Thanks to eight big screws, 7 are already removed in this picture and one is still loosely in place to avoid the case back moving around while photographing. Jaeger-LeCoultre deserves a compliment for not over-tightening those screws on the case back. With a Bergeon watchmaker's screwdriver - please make sure the size of the screw driver matches the screw - the screws can be easily removed. Sometimes those screws are tightened so hard, the screwdrivers bend.
A remark to the quality of the photos. These pictures were taken during watch work. I opened a couple of my more expensive quartz watches that afternoon in October 2003 and to proceed with the work and make sure nothing bad happened to those rather expensive pieces, I did not care too much about the quality of the pictures.