Mike Music Self-Adhesive Pickups Piezo Transducer With 6Pcs Celluloid Guitar Picks, 3 In 1 Microphone Contact & Endpin Jack 1, 4" For Electronic Acoustic Guitar Violin Ukulele (Bfriend)

3 Transducer Pickup System fit for most string music instruments, amplify an upright bass, banjo, violin, ukulele, viola, cello, mandolin, and a resonator guitar The plastic squares is a self adhesive block to mount the extra wire in your box, the best material will be very durable The plastic squares is a self adhesive block to mount the extra wire in your box, the best material will be very durable Cable Length: approx. 57cm/ 22.44", 3-pack Piezoelectric Disk Dia.: approx. 27mm/ 1.06", Endpin Jack Dia.: approx. 6mm / 0.24" Material: Plastic, Electronic Part: Metal, Color: black lines, red tone