The 4.5 size upholstery zipper chain is perfect for cushions. Its strong and every inch has been laser inspected for any imperfections.
This chain is the easiest chain to get the slider on. To get the slider on simply back the slider onto either end of the chain, then while pressing down with your index finger, begin to pull the chain apart forcing the slider to back on as the chain pulls apart. If you find this too hard to do you can try the direction for the size 3 zipper chain, just click on that product to read how.