This listing is for one cork black checkerboard phone grip. (Yours will be in the same print but possibly a different cut).

The grip is meant to attach to a plastic phone case. Just take your phone out of the case, wash and dry your case, use rubbing alcohol & a cotton puff to rinse the area you will place the grip and let it air dry. Once dry carefully remove the backing and place it directly where you want it to go. Press firmly. Then you can put your phone back in it. I have never needed to do this, but if you are an active person, you may want to consider using E6000 glue for a permanent hold.
 
The grip itself is a 1 1/2" circle and 3/8" deep when closed. It is just under 1" deep when open. The grip allows you to hold your phone between two fingers or is a stand when your phone is in the horizontal position.