Damasko usually provide a suitable Damasko branded tool with the bracelet - see their website. Though I don't think it's a special size or anything and small torx screw drivers are easy to find - I don't have the watch anymore so I can't confirm the size you need.
Do you have the bracelet or are you thinking of ordering one?
Personally, I'd never use the bracelet and would only wear the watch on the leather strap. This is because my Damasko bracelet rusted and wrecked my watch case.
Another problem is having the correct lug pins and spring, if you lose them or even one part, you've stuffed as the end links rattle about with a conventional spring bar. Attempting to get spare parts is like trying to get blood out of stone. I gave up after months of asking and sold the watch at a loss to be rid of it.
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