Shallow Saucer 11" White Acrylic (3-1/8" Deep, 12" OD, 9-3/8" Fitter) (item # 4114-SI-S11W) This diffuser family utilizes a shallow saucer design to give maximum light output in a classic shape. Measurements: 12" across, 3-1/8" high, 9-3/8" inside ring.