Ok, now I'm massively impressed by Sinn, even moreso than I have been over the years.

The tegimented 22mm push button clasp arrived, but it's different from one I had many years ago. It has a normal spring bar connection for the silicone at the six o'clock end, but at the 12 o'clock end it has a jaw which clamps shut on to the silicone, using the metal bar fillers as a 'stop'.

Basically it takes away any "I've cut it too short" anxiety and renders the silicone completely adjustable. Superb idea. And the jaw clamp really is hugely strong.

Pictures are worth a thousand words...