Features: Dual concentric stacked knobs to achieve Tone & Adjustment on the same knobs. Fit for electric guitars and bass. Made of alloy metal providing long durability. Package comes with 2 sets; there are 3 colors for option -- silver/ black/ gold. 100% Brand new and testing is fine. Specifications: Material: Alloy Metal Color: Silver/ Black/ Gold (optional) Item Size: Refer to the picture for detailed size Item Weight: 30g / 1.06oz Package Size: 7 * 5 * 2cm / 2.76 * 1.97 * 0.79in Package Weight: 62g / 2.19oz Package List: 2 * Dual Concentric Knobs