Hart & Cooley® Floor Register, 2-Way, Series: 421, 6 x 12 in, 11-5/8 in Duct Width, 5-1/2 in Duct Height, 7-1/2 in Overall Length, 13-1/2 in Overall Width, 48 sq-in Effective Area, 1/2 in Blade Spacing, Steel, Golden Sand Enamel, Domestic