Crash Protectors or bungs, sliders . Lots of names for them. Anyway they are about £58 a set on ebay for my 92 NC31. I bought a set for a 98 Hornet 600 at £29 . The 130mm bolts are too short so 2 M10 180mm allen bolts £4 , and a stack of about 7 washers on each side to space the bungs out from the frame and hey presto a set for £33. I also fitted a couple of nyloc nuts instead of the ones supplied. Ok they may not be R&G but will save the bike in a slow spill or as in my case, just falling over. The Hornet bungs can be found for about £15 from China if need be.