This Zenith El Primero Striking 10th is one of a limited edition of 1969 watches made in 2011 with a 42mm stainless steel case and a silver chronograph dial with three different coloured sub-dials. This watch is 99% perfect in every way and I would be surprised if it had been worn more than a few times and then very carefully.
The movement of the El Primero Striking 10th is something special so it's great that you can see it through the sapphire case back. Every 10 seconds that the chronograph runs, the seconds hand makes one circuit of the dial and special calibrations on the rehaut allow you to easily read fractions of a second.
Just tested by Rolex & Omega certified watch specialists Michlmayr & Co and this Zenith El Primero Striking 10th is running within COSC spec.