The Edwards Signaling SD-T24 SD Series SuperDuct is a 24" air sample tube designed for efficient use with duct smoke detectors in tight spaces, being under 2" deep. It features a PCB-mounted photoelectric sensor equipped with onboard intelligence and patented environmental compensation technology for reliable and stable performance. This device is built for high air velocity ducts up to 4000 ft/min and pairs with standard Kidde Intelligent smoke detectors. Installation is simplified with a prewired detector base that the detector easily plugs into. Compatible with the Four-wire Duct Smoke Detector SD-4WJ, it provides wide smoke sensitivity ranging from 0.79% to 2.46% per foot obscuration. Upgrade your fire detection system with this advanced, easy-to-install SuperDuct tube today!