Our BL-6B and BL-10B Motorized Steel Bells are designed for today’s fire alarm applications. The durable steel construction provides loud resonant tones necessary for fire alarm installations. The BL-6B and BL-10B bells use a varistor suppression element to prevent RFI and EMF noise problems to modern fire alarm control panels. The motor used on the BL-6B and BL-10B bells operate at a very low current (20mA) to maximize the number of bells per circuit. Both models are equipped with a pigtail connection for wiring. Both the BL-6B and BL-10B mount on a standard 4" square electrical box for indoor use or on a BB- 206WP weatherproof backbox for outdoor applications. Mounting on a 4" octagon outlet box requires the MP-101 Universal Mounting Plate. The durable steel construction provides loud resonant tones necessary for fire alarm installations.