(157) Marks "Hi-Security" Lock: Gutted
Channel: Alex Blate
Date: 2013-02-03

I've been working on this bad boy for a while. It's a 6-pin-tumbler lock with side finger pins that control a sidebar. 

The top pins are all spools with very thin rims, the plug is counter-milled, the pin chambers in the shell are a bit rough, and the tolerances are pretty good... so just the base lock is a jolly hard pick. Adding to the fun, the sliders give almost zero feedback. Each one has two possible positions -- a true gate and a false gate -- with a little hump in the middle. If you're not perfectly aligned, the hump holds the sidebar away from the pins, preventing feedback on its neighbors. The finger pins are also *not* spring-biased, so they're hard to feel for and touching them pretty much guarantees moving them. 

Even with just 3 of the 5 finger pins in place (no pin-tumblers) and with the key in front of me, it was nearly impossible to release the side bar.

I've never seen this model of lock before (though it may be a copy of some other design)... but it is made in the USA and is one of the more secure locks I've encountered thus far.