Warning. a long review. I bought it because the original button on my left joystick came loose. I first put on one of the shorter grips, did a "test ride" and found that they slip off easily as you will hear in other reviews. I replaced the shorter handle with a larger one and found that it doesn't really fall off (works more than enough for gaming) but it can be detached if I want to take it off. Then I put the shorter grip on my right joystick (the joystick that still had the original grip) and noticed that it didn't fall off. Therefore, the larger ones at the end should be used for thumbsticks without the original grip, and the shorter ones are used to reinforce the grip that is already in place.