Thanks Jan, they are the gsxr calipers, mine are K1 I think.
Pic below-
They need adaptors but otherwise bolt straight on.
You will need the suzuki mounting bolts or you could go bling and fit titanium ones like I have (the only bit of bling on the bike, it's for go, not show)
I also tried Fireblade Nissins-
These require a bit of work to the caliper body otherwise they foul on the disc and the same adapters as the gsxr. Personally I think the 'blade calipers are worth the extra work, I preferred the feel and I think they look better.
Both are a great improvement on the standard calipers and are cheap on ebay.
Mike
Need Break down cover? P.m. me.