View DSB-123SD Options Door Size H × W (in.) Door Size H × W (mm) Wall/Ceiling Opening H × W (in.) Shipping Wt. (lbs.) Shipping Wt. (kg.) 12 × 12 305 × 305 12 1/2 × 12 1/2 35 15.9 16 × 16 406 × 406 16 1/2 × 16 1/2 44 20 18 × 18 457 × 457 18 1/2 × 18 1/2 49 22.3 24 × 24 610 × 610 24 1/2 × 24 1/2 65 29.5 36 × 24 914 × 610 36 1/2 × 24 1/2 80 36.4 36 × 36 914 × 914 36 1/2 × 36 1/2 115 52.3