Ok, I've seen references to lock that seagal marketed as "pick-proof" in the early 1940's. Not "Jimmy-Proof" like the standard Segal Drop Bolt. Anyway, does anyone know anything about this lock? What style cylider is it?
Apparently it did resist picking with standard tools, but it could be done with specialized equipment & techniques. My thoughts are that it might be a pin tumbler mechanism with security pins and or additional pins, a rotating disk mechanism like Abloy, or a lever lock of some sort.