Basically, the pins are made of glass, with the driver pin being a serrated, spool or mushroom pin, and the key pin a mushroom or spool. When the correct key is inserted and turned, great, but when a pin binds through the application of torsional force, it snaps, bits of glass gum up the lock, and once the pick/foreign object/etc is removed, a metal rod contained in the spring drops down, preventing someone from just using a screwdriver to bust the pins and open it. Of course, once this happens the lock is ruined and needs to be drilled, but there you are.
I’m hoping the diagram will explain things better, any feedback would be great.
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