This metal purse frame is 4 3/4" x 1/2" There are some directions with the frame but basically you make a casing and put the arms through it, then put the nail into the open end to close it. Note that when putting the two arms through the casings, you must start and push them through together. They can't go through the casings one at a time because the metal won't bend enough :-)
Note: Once the nail is in place it isn't easy to remove, so check you are happy before you push it in!
These frames are also called squeeze frames, because they pop open when you squeeze the ends between your index and thumb. However this one is a bit long for that so I like to sew a tab or a charm to each side of the top middle to pull it open with. Let go and they pop closed.