SMART KIT 1018 GUITAR TREMOLO is a TREMOLO with professional specifications. It adds a wonderful effect to your guitar. Music lovers will be thrilled with the capabilities of this KIT. The circuit has a very low power consumption, so with one battery you can get several concerts. The TREMOLO speed and rate is adjusted. Power supply: 9 VDC. Input sensitivity: 200 mV. Frequency TREMOLO: 1-20 Hz. Response: 10 Hz-16 KHz