Key Specifications and Uses of these Buttons: Facilitates Four-Finger Play: Provides you with additional mechanical buttons (L1 and R1) at the top of the phone for quick and smooth aiming and shooting. Metal Buttons: Feature fast response and high accuracy with every press. Flexible and Adjustable Design: Includes a screw or clip on the back to securely attach them to various sizes and models of smartphones (iOS and Android). 100 pieces available. Selling as a whole lot.