Features: Double Pickup: Dual microphones capture the sound detail, and the piezoelectric pickup is capable of picking up much wider audio frequency. EQ Adjustment Function: Catering to different guitars and offering the suitable sound effect. With phase reversal knobs, so both plus-phase and anti-phase sound effects are available. Easy Installation: It features exquisite buckle design, guaranteeing the pickup to be buckled on the verge of the guitar sound hole firmly, no drilling required, harmless for guitars. Minimum Noise: Due to GGP-01’s shielding and strong anti-interference capacity, its background noise is quite small. GGP-01 pickup is suitable for 36-42 inches classical and acoustic guitars; Long battery life, can operate for more than 40 hours in a row. Specifications: Material: Metal+Plastic Color: As The Picture Shows Package Weight: approx.160g Size: approx.8.2x5.8x2.4cm/3.22x2.28x0.94in (More Size Detail, Please See Photo.) Package Includes: 1 Set of Acoustic Guitar Pickups note: Please allow 1-2cm error due to manual measurement. Please make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks!