Furnish cable operated remote controlled volume dampers in inaccessible branch ducts feeding continuous linear diffuser plenums and where otherwise indicated. Reference architectural drawings for locations of gypsum board, spline etc. ceilings. Dampers shall be adjustable through the diffuser face with standard tools, providing positive balancing of multiple airflows to maintain design air throw and noise criteria. Extruded aluminum damper shall be pivot actuated by a brass plated rotary cable which is supported at the damper end in an extruded aluminum-bearing bracket. Rotary cable shall have a minimum torque service factor of 200% when installed in accordance with manufacturer furnished instructions. Cable assembly shall snap-fit into damper for one piece installation with no linkage adjustment required or miscellaneous small parts. Accessible cable end shall be secured with a factory furnished nylon clamp, allowing maximum placement flexibility. Positive, direct, two-way damper control shall be provided without sleeves, springs, or screw adjustments (that may loosen after ceiling closure). Damper sizes greater than 24"x20" shall be fabricated in sections with one cable operator per section. Cable operated dampers shall be Metropolitan Air Technology LLC. Model #RT-100 (or RT-110 for sectional units).

US Patent #5,702,298. Canadian Patent #2,185,311.