Siemens GND226.1U/F, OpenAir GND Series Electric Damper Actuator, rotary, spring return, 53 lb-in (6 Nm), 120 Vac, 2-position control, 15 sec run time, Fire/Smoke, dual auxiliary switches, electric fuse link connection. Designed for UL Listed Smoke Control Dampers and for Combination Fire/Smoke Rated Dampers. ASK79.xxx Electronic Fuse link is temperature specific and sold separately.