Features:  Sound Hole Mounted Pickup: it adopts magnetic induction coil to pick up the sound, which is suitable for steel string folk guitar.  Perfect Sound Effect: the new generation RX double coil technology greatly increases the dynamic and hierarchical sense of sound.  Simple Operation Interface: detailed humanized control design, simple and innovative. The main volume and timbre can be adjusted independently to meet your personalized needs for music.  1 Minute Quick Installation: clip the pickup into the sound hole and tighten the two screws to complete the installation. The tail nail output line can be installed without drilling hole(the sound hole extends to the tail nail) or punching (the tail nail output is connected line from the inside).  Power Supply: just powered by a 1.5V AAA battery, the usual battery is easy to buy and replace.  Wide Compatibility: it is suitable for guitar installation with sound hole diameter of 95-110mm.    Specifications:  Color: Black / Blue / Gray (Optional)  Material: Alloy  Power Supply: 1 * 1.5V AAA battery (NOT included)  Suitable for: 95~110mm soundhold guitar  Item Size: 102 * 42 * 22mm / 4.02 * 1.65 * 0.87in  Item Weight: 130g / 4.58oz  Package Weight: 194g / 6.86oz  Package Size: 12.3 * 6.6 * 5.2cm / 4.84 * 2.60 * 2.05in    Packing List:  1 * Pickup  1 * Tail Nail Leather Cover  1 * Output Tail Nail  1 * Cross Screwdriver  2 * Clip