Short 30-Second Travel Time Available — provides a quick response for two-position zone applications 35 dB Nominal Audible Noise Rating — meets the audible noise requirements for open-ceiling environments Synchronous Drive — provides a constant rotation time that is independent of the load 100,000 Cycle Rating — provides years of trouble-free service Direct Shaft Mounting with Single-Screw Coupler — reduces installation time and provides three-point shaft gripping