The RYOBI 1 Gallon Chemical Sprayer Tank is compatible with both the RYOBI 18V ONE+™ 1 Gallon and 2 Gallon Chemical Sprayers. Mix your fungicide, herbicides, or pesticides into their own designated tank so you can store your chemicals separately when not in use. Equipped with a cap that doubles as a mixing cup, this spare tank accessory is built for convenience from prep to clean up. Simply attach this tank to your existing RYOBI 18V ONE+™ 1 Gallon or 2 Gallon Chemical Sprayer, start and spray without manual pumping.