The EP-01-JG is a small, light weight piezo sensor that is meant for one time installation on an instrument's soundboard. The pickup comes with 18" of shielded cable and is supplied with a chrome endpin jack and gold strap button. Since this unit is meant primarily for protected interior installations, the piezo element is not 'potted', but is instead covered with an acoustic foam pad. Due to the nature of the piezo and the fact that it is not a 'potted' unit, this pickup has great output and full response. No preamp is required. This pickup is not suggested for stage use. Specifications -- Sensor diameter: 0.59" (19/32", 15mm); Lead wire: approx 18" long; Soldering required.