The Model XP312 is a 3 Gallon Backpack Sprayer w/Piston Pump & Santoprene Cup - The XP Series Backpacks are ultra-comfortable, lightweight, robust and professional-grade. Backpack sprayers require less pumping to achieve maximum operating pressure, only 8 pumps to 45 psi reducing operator fatigue. Popular with home, farm and ranch owners who need performance in a lightweight sprayer and tested to over 1,000 hours of continuous operation.