6 x 19mm book rings to use on your Resize Ramp. Feel free to buy in bulk on eBay if you wish! If the book rings eventually wear loose and do not fasten well, do not use them on your ramps, replace with newer stiffer ones.
If you want to adjust the ramps permenantly, use 100mm tie-wraps, l which you can also get on eBay. Remember to sand the cut edge when you trim off the excess of the wrap or your Fuzzy could get a nasty cut.
If you have limited dexterity in your fingers, they could be a bit fiddly and sometimes a bit tight, but some gentle bending should make them easier to open :)