This is a Shimano RX100 - model BR-A550 - front and rear brake set with a pad drop of 47-57mm.
Removed from a 1999 Woodrup due to upgrades, although these appear to have had limited use. One of the cable guides is non-original and the 'Super SLR' badge is missing from the front brake. Fully working when removed.
Happy to post, or can be collected from Dewsbury, West Yorkshire.