Back Pack sprayers are ideal for larger rose gardens because they are easy to carry, require less effort to pressurize, and have larger capacities than most regular pump sprayers. Tough, one-piece blow molded tank, won't leak at bottom; translucent for viewing liquid level; molded-in base provides lumbar support to protect sprayer when on the ground; Large, easy-fill opening with fine mesh screen keeps out debris. Powerful, corrosion-resistant poly piston pump maintains high pressure with less work. Adjustable for left or right handed pumping and spraying. Roto Valve on/off control valve rotates 360 degrees for up or down spraying with no bending or wrist twisting. 4 gallon capacity.