The clasp is a No.27 sometimes also marked 1120/116 and is designed for an Omega Geneve Chronostop mesh band.

The stem/crown was removed from my watch as part of the service by Omega Bienne - it was functioning OK before removal and my Chronostop is a 1969 146.009 cal.920. This may also fit other models but not sure which.

Note the crown has a little bruise at 1 o'clock position.

Clasp £55 within the UK.
Crown/stem £25 within the UK.

If you buy both items deduct £5.
Please add an additional £4 for post if you live overseas.

Payment (GBP) by Bank Transfer or Paypal as a gift please. This includes Royal Mail 2nd class signed for delivery within the UK.