The Scotty 4000 pump is a single action pump. The pump has a brass pump chamber protected by an engineering grade polymer sleeve. No tools are required to disassemble the unit, it can be completely disassembled by hand for in-the-field maintenance.
The Backpack (4002A) has a capacity of 5 US gallons (19 litres). Manufactured from a strong polyester reinforced fabric, protected by a thermoplastic polymer layer. It has a 4" filler port with a removable debris screen, 2" wide shoulder straps and 3" wide shoulder pads.
(Meets UL and other back pack pump specifications)