Containing both a 24 VDC supply and a 20 A line voltage relay for most models, the Leviton® compact power pack provides low voltage power and line voltage control for Leviton® occupancy Sensors. Versions include auto ON and manual ON inputs for occupancy sensors, hold ON and hold OFF capabilities and a local input for momentary or maintained dry contact switches. The OSP power pack series is also used to supply power to the OSA Add-A-Relay model. The power pack conveniently mounts in a knockout hole of a standard junction box. The unit can be placed inside or outside the junction box with a simple twist on nut. The internal relay can control up to 20 A at either 120, 230 or 277 VAC ballast load, 15 A for 347 VAC ballast load.