A modern ballast for powering 4 f32t8 workplace lamps. Typical diameters are t12 or t38 (1 1⁄2 in or 38 mm) for residential lamps with magnetic ballasts , t8 or t26 (1 in or 25 mm) for industrial power-saving lamps with digital ballasts, and t5 or t16 (5⁄eight in or sixteen mm) for very… Read More