Description Toto Aquia 2.5 inch Dual-Flush Canister Toilet Repair Kit | One-Piece Toilets Flush Valve: 2.5 inch flush valve with adjustable 8-12 inch tall overflow tube. Fill Valve: 7/8 inch fill valve adjustable from 8-12 inches tall. Canister: The durable polymer canister valve is designed for one piece toilets with 2 inch flush holes. Dual-Flush Button:  Top button dual flush canister for half and full flushes. Easy Installation: Installation hardware included for install in many common brands.