Item Type: Electric Guitar Roller String Tree Material: Brass, zinc alloy Size: Approx. 1 x 0.9 x 0.26cm / 0.4 x 0.35 x 0.1in 1[String Retainers Tree] These string retainers are the type with small rollers that help maintain intonation and prevent string breakage. 2[Mounting Screw] The string retainer comes with 2 mounting screws and is a good replacement for broken, dirty or old wire grippers. 3[Reduce String Stress] The rollers on the string retainer reduce the stress on the strings, which keeps the guitar in tune longer. 4[Prevents Wear and Tear] The string retainer prevents string wear and tear, thereby extending the life of your strings. 5[Durable Material] The string retainer tree is made of brass and zinc alloy, hard wearing and compatible with electric guitars and basses.2 x Electric Guitar Roller String Tree 2 x Screw