The Yard Tender sprayer is capable of reaching up to 168 psi with a repairable internal piston pump. This 4 gallon unit will stand up to products such as pesticides, herbicides, oil based, solvent based, sealers amp; stains, wettable powders, diesel fuel and chlorine-based products. Like all SP Systems backpack sprayers, repair parts are always available for the Yard Tender 189.