The Chapin Wide Mouth 4-Gallon Backpack Sprayer has a 6-Inch opening for easy filling and servicing of the pump. Chapin has a wide assortment of backpack sprayers but the 63800 is unique with it"s large opening and other great features. Sturdy poly wand that is rigid enough to keep from sagging - flexible enough to withstand bumps. Built-in carrying handle makes cap removal easy and carrying the unit a breeze. Pump handle attaches for left or right hand use. Enlarged strainer basket with gasket helps fill without splashing. Translucent tank helps monitor fluid level. Metal base rails allows unit to stand upright while unattended and during storage. Large serviceable pump cylinder. Reinforced hose and cushion grip shut-off with lock-on/off feature and Viton O-rings. Deluxe Padded Straps with waist/chest strap.