serrated pins how we hate you. Serrated pins are a high security pin that is really a pain.
Serrated pins are as you guessed serrated Each little serration in the pin is an edge that will catch on the sheer line of the lock. Each time it catches you have to try and lift this pin a bit higher.
The problem is that when you try to lift it other pins that you have already lifted might fall. It is highly frustrating and has you constantly resetting and starting over.
The first progressive serrated has three pins 2 standard and one serrated.
The second lock has 5 pins, three standard and two serrated. If you want to fill an evening with frustration progressive serrated locks are for you.
Both locks are laser engraved so you can keep track of what's in your collection