This listing is for a PAIR of pulleys. I do recommend you replace in pairs to make both sides even. These are actually pulleys from a Total Gym, but I have had good luck with Total Trainer customers using these to replace worn, broken or gravely pulleys. You have to slightly open up the hole that the pin goes through with a drill. It almost fits naturally, but a slight increase in the size will make it perfect. I know replacements are hard to find, so based on the success of others I decided to offer these.