This BugsGear cicada contact pickup equipped internal preamp,
lithium battery, 1/4" output and micro USB recharge port.
It can be attached to any acoustic instrument and used.
Completely overcomes the disadvantages of conventional 
passive pickups.
It Keeps low noise no matter how long the cable to the amp
so, suitable for sue on the live stage.
Stringnet designed this pickup inspired by loudly crying cicada 
clinging to a tree during hot summer.
Spec
Size       : 4Cm X 4Cm X 2Cm
Input      : Piezo dis pickup
Output   : 1/4" guitar socket
Control   : Dial volume
Power     : 3.7v 200mA lithium rechargeable battery
              Play last 10hours
Recharge : 2 hours
Color       : Black (prototype color is white but shipping in black color)