SelecTone Amplified Speaker, 120VAC - Available in 24VAC/DC and 120VAC. Solid-state circuitry. Built-in gain control, adjustable between 64 dBa to 88 dBa at 10 feet (74 dBa to 98 dBa at 1 meter). Flush or surface mount. Type 3R enclosure when used with the WB backbox. UL and cUL Listed, CSFM Approved.