Amazon.com: Metal Marshmallow Piezo Contact Mic (White +14dB) : Musical Instruments
Piezo Contact Microphone 3 Transducer Pickups with end pin jack for Kalimba G1C5 | eBay
Contact Mics Contact Microphones Piezoelectronic Transducers Piezo Microphones Weirdo Gadgets Designed by Crank Sturgeon Manufactured by Huso Solutions since 2007