It's pretty simple and very close to Glock's "safe action" system. The FP block sits in front the leg on the striker. Spring tension holds the safety lever closed preventing the striker from moving forward enough to touch the primer. As the trigger is pulled, a triangular tab on the triggerbar acts as a ramp, pushing the FP safety to the side and holding it out of the way until the striker releases from the trigger bar and goes forward. Like the Glock, the striker is not fully cocked when the trigger is forward. So in the unlikely event that both the FP safety and triggerbar or striker leg break at the same time, the striker won't have enough energy to ignite the primer. Most other striker fired guns (XDs, M&Ps, P320, VP9, PPQ, etc) use a fully cocked striker and rely on a trigger spring to reset the trigger. In the Glock and P10, the striker re-engages the trigger as the slide comes forward. That's why the Glock and P10 have such positive reset. And while people bemoan the CZ for cribbing off Glock's design, when you look at the new 5th Gen Glocks, their revised FP block is no longer a round button, but ramp shaped like on the P10.