Guitar Pickup With Volume Control, Piezo Contact Microphone Transducer For Acoustic Guitar Pickup Product details 2.5mm output jack Self-adhesive pads 3 meter cable Volume adjustment knob 6.35mm(1/4 inch) male plug Features No need to punch hole. No battery needed. Available for acoustic/classical guitars, cellos, banjos, ukuleles, mandolins, violins and more. Mini design, Brass plating material plug, anti noise and disturbance. Nice Feature: With self-adhesive sticker on back, mini piezo pickup comes with 4 extra sticky pads for replacement, and a detachable 10 feet long(3M) pickup cord: one end of pickup cable is 2.5mm male mini-jack for plug into the pickup, another is 6.35mm male plug for connect to your sound box/AMP. There is a volume knob on the compact pickup adjustable for avoiding squeal feedback. Easy to Install: It takes about one minute to mount. There is no need to punch holes on your musical instruments, no batteries required. Just move the pickup to find the best tones when strum, then peel off the pickup backing paper and stick on the surface of the instrument. Connect pickup and amplifier by pickup wire. Widely Use: The stick-on transducer pickup perfect for guitars, mandolin, violin, ukulele, banjo, sitar, harp, hammered dulcimer and any acoustic stringed musical instruments. Sounds crisp, bright and fatter sound, without distortion. Cute Gifts: The portable acoustic pickup is a great birthday gift, party gifts, back to school gifts and Christmas gift for music students, guitar player, musicians, beginner, occasional performer, guitarist. Warmth Tips: When the lightweightt pickup is optimally located on the instrument, you can get the clean and smooth sound quality. (Position reference: near the bridge or sound hole, etc). Please stick the piezo pads on instrument tightly to receive sound perfectly.