Remember those unsigned single button chronographs from Breitling and Omega we showed you a few months back? How about the Omega signed RAF single button chronograph we found way back when? Good, because we’ve found another one hitting the block at the upcoming Bonhams auction on Dec. 14th in London.

We’ve explained how rare this particular watch is, in fact this is only the second to come across our radar. The details on this example are impeccable, considering it was issued in 1962 and likely saw some active duty in the Canadian Royal Air Force in its day. Inside is the manual winding Cal. 2221 Lemania chronograph, which is made that much cooler by the fact that it hacks. Adding a little more character are the lume pips extending into the dial and the engine turned subsidiary dials for the running seconds and 30 minute recording. The steel case has a screw back engraved with military numbers HA-62-1361 6W/16 and 34/62 inside.

Pre-auction estimates are at  £3,500 – 4,500 ($5,500 – 7,000) which would be a great buy considering the last one we found sold for $14,000 at a Christie’s auction.  For more info on this watch and to register to bid, click through to Bonhams online catalogue