The pocket frame is a frame that comes in two pieces. The large piece is composed of the bottom horizontal piece with the two sides of the frame extending on the left side and the right side. They basically make a squared u shape. The top piece is the final piece that fits horizontally on the top to complete the frame. It stays in place because of the magnet at each inside that attaches itself to the magnet on the top right piece and top left piece. (Magnet is not visible once you place this piece in place to complete the frame). This enables you to open up the frame and slip in whatever accessory you want to use. For example in my frame I put the back piece that is a form of a “shiplap pattern” or you can have the reverse side facing out and that is a “brick pattern”. I have the smaller frame and like it so much tonight I have ordered the larger size. I hope this helps.