System Sensor SGWL — L-Series compact wall strobe, white, clear lens, FIRE marking.The compact L-Series housing is over an inch narrower than the standard one and fits a single-gang box, which is why it gets specified in corridors, stairwells and retrofits where no 4-inch square or double-gang box was ever installed. SGWL is a strobe only — no horn, no sounder — so it suits places where visible signalling is required and audibility is already covered on the circuit. Seven field-selectable candela settings: 15, 30, 75, 95, 110, 135 and 185 8–17.5 V (12 V nominal) or 16–33 V (24 V nominal); 1 flash per second Current draw at 24 V DC: 43 mA at 15 cd rising to 222 mA at 185 cd Indoor, wall mount only; 32°F to 120°F, 10–93% non-condensing 5.26" × 3.46" × 1.93" including lens Compact units use a different mounting plate from standard L-Series units and fit only a single-gang box or the SBBGWL compact surface back box — the standard SBBWL will not work. Only 15 and 30 cd are listed for 12 V.