20 pieces of compact disc transducers with copper backing, designed as buzzer sound microphone elements and contact pickups for musical instruments and electronics. These transducer discs convert mechanical vibration into an electrical signal, making them suitable as guitar pickups, drum triggers, and general sound sensing elements for DIY projects. Key benefits Ready supply: 20 identical transducer discs so you can outfit multiple instruments, build several projects, or keep spares on hand. Direct vibration pickup: Captures contact vibrations from surfaces and strings to produce a clear electrical output for amplification or triggering. Easy wiring and mounting: Copper sheet backing provides a solderable pad for reliable connections and a flat surface for adhesive or mechanical mounting. Versatile use: Works for instrument pickups, electronic drum triggers, trigger pads, hobby electronics, and sound detection circuits. Practical for low acoustic signals: Responds to low frequency and contact vibrations, useful where air microphones are impractical or unwanted. Product attributes Quantity: 20 pieces Form factor: thin round disc transducers in a compact disc shape suitable for contact mounting Backing material: copper sheet for soldering and secure attachment Function: converts mechanical vibration into an electrical signal for use as a pickup, trigger, or sensor Compatibility: suitable for acoustic and electric guitars, percussion trigger systems, piezo preamps, audio interfaces with impedance inputs, hobby microcontroller sound projects, and general sound sensing applications Installation: solder wires to the copper pad, attach disc to the instrument or surface with double sided tape, adhesive, or mechanical fastener; no special tools required beyond basic soldering equipment Performance notes Designed to sense contact vibrations rather than air pressure, offering clearer pickup of string and surface resonance. Appropriate for low frequency and percussive signals where direct contact sensing improves response and reduces ambient noise pickup. Performance depends on mounting method, connection quality, and preamplification or input stage used. Typical applications Acoustic guitar pickup: Mount the disc to the guitar bridge or soundboard to capture string vibrations directly for amplification or recording. Electronic drum trigger: Attach to drum heads or shells as a reliable trigger sensor for electronic drum modules and samplers. DIY music electronics and sensors: Use in pedal circuits, trigger pads, soundactivated projects, and student electronics kits where compact contact sensors are required. What you get A pack of 20 identical disc transducers with copper backing, ready for soldering and mounting on instruments and project surfaces. This pack provides a practical, lowcost way to add contact pickup and trigger functionality to multiple instruments and projects while keeping installation straightforward and repeatable.