U-Change
To look at this lock, you might think KW smartkey. Though it would fall into the same user re-keyable category as the smartkey, it has no sidebar and in terms of construction and durability it is superior. Instead of pushing a portion of the plug backward to allow the pin/wafer sets to realign at a new height, the change tool in this one acts on each pin individually separating the keypin elements that make it adjustable.
The brass piece farthest to the left that looks like captain Crunch's hat, is the rocker. When turned to 90 degrees the rounded portion of this piece is forced up into the bible as the change tool seperates the silver tab from the shell of the keypin during rekeying. There are only 4 depths, but while that is limiting, it's design is a solid construction. Deep grooves, thick round tabs, and an increased pin diameter leave no room for this one to be forced open.
This is the exploded pin stack.
In comparison to the keypin, the driver is nothing out of the ordinary. Other than a larger diameter and depression in the top to allow for a greater range of movement without crushing the spring it is standard.
A very interesting mechanism to examine... enjoy