Description Gerber Avalanche Toilets One-Piece Model #21-014 Repair Kit For One Piece Toilets | Adjustable Flush and Fill Valves Included Flush Valve: 3.15 inch flush valve with adjustable 6-10 inches tall overflow tube. Fill Valve: 7/8 inch fill valve adjustable from 8-11 inches tall. Flapper: The durable silicone flapper valve is designed for one piece toilets with 3 inch flush holes Easy Installation: Installation hardware included for install in many common brands.