product manual: This pickup can work well on guitar amplifiers and other musical instruments (such as cello, banjo, ukulele, mandolin, banjo...). . The pickup is very sensitive and can restore the fidelity of the instrument, but the sound depends on the quality of the speakers. If you have any questions, please feel free to contact us. specification: Female plug: 1/4" [6.35mm] Cable length: about 10.8 inches Sensor: Use a double-sided faucet to connect the sensor near the sound source. Self-adhesive Velcro: used to fix the jack on the surface of the guitar. Packing size: 5.5 inches x 4.6 inches x 0.7 inches Color: black and red Weight: 10g On the packaging 1 TD-11 piezoelectric pickup 2 x stickers"