Oster Microwave Glass Turntable Plate / Tray 12 3/4" This microwave plate ONLY fits the Oster models listed below. If you are unsure about compatibility please email us with your model number BEFORE ORDERING. Glass turntable plate / tray for Oster microwave ovens. Measures approximately 12 3/4 inches in diameter. The inner ring where the turntable wheels fit has an outside diameter of 9 7/8 inches.