Feature: 1. Applicable for 9V battery, suitable for acoustic guitar and bass pickup. 2. Made of plastic, durable and wearable for long service time. 3. Great accessory for guitar pickup, excellent replacement for guitar players. 4. With a maximum size of 5.6 * 5 * 3.1cm/2.2 * 1.97 * 1.22in. 5. Easy to mount, convenient to assemble it. Specification: Features: Applicable for 9V battery, suitable for acoustic guitar and bass pickup. Made of plastic, durable and wearable for long service time. Great accessory for guitar pickup, excellent replacement for guitar players. With a maximum size of 5.6 * 5 * 3.1cm/2.2 * 1.97 * 1.22in. Easy to mount, convenient to assemble it. Specifications: Color: Black Material: Plastic Item Size: 5.6 * 5 * 3.1cm / 2.2 * 1.97 * 1.22in Item Weight: 20g / 0.71oz Package Size: 12 * 7 * 3.5cm / 4.72 * 2.76 * 1.38in Package Weight: 22g / 0.78oz Package List: 1 * Battery Case Package List: 1 * Battery Case