Description: This set of heads mainly adjust the melody of strings. The tuned bass string does not loosen easily. With these tuning pegs you can strings fast and accurately. High quality internal gear it s effective to prevent screw slippage. Suitable for 12MM/0.47inch opening according to the product size details to buy. These tuning pegs are electric bass and good rust prevention. Specification: Color: Material: Metal Size Chart: String Diameter Size: Approx. 8mm/0.31inch Package Includes: 4 Pieces 2L2R Bass Note: 1.Please allow 1 to 3mm error due to manual measurement. please make sure you mind before you bid. 2.Due to the difference between different monitors the picture may not reflect the actual color of the item.