Aftermarket Flush Ball Seal Properly Fit Models: 300/ 310 / 320 Toilet Easy to Install and Replace Your Leaking Flush Gasket Seal, Dimensions: 4 Inch Outer Diameter. 2.75 Inch Inner Diameter. 0.2 Inch Thickness/Height. High Quality Material to High Performance, , Anti-Friction, Good Tightness, no Leakage Our flush ball gaskets are a for 300/ 310/ 320 RV, motorhome and trailer toilets. These flush ball seals replace flush ball seal kits # 385311658. DOES NOT FIT MODELS: 210, 510 or Other Models Not Mentioned. Color: Black Material: Silicone Package Contents: 6 x Toilet Flush Ball Seal Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.