Take the cap off, put the cap on, take it off, put it on, where'd the cap go? I know the cap can be a pain but there's nothing worse then losing one. If you've lost yours this is a perfect replacement cap. It's actually nicer then the original one, it's thicker, stays on better, and comes with a string. It will come to you in two pieces, you put it together and put it on the camera. The string has an elastic band that loops around the strap and acts as a shock absorber so you won't loose it. Both items are brand new and sure to last a long time.