Rotary Vane Pumps with Manual Nozzle, 20 gpm, Rotary Vane Amp ORS NASCO and valve packing nuts Extra wide opening and valve packing nuts Extra wide opening offset model is ideal for securing drain nuts on sinks and tubs Provides reliable protection from airborne debris Curved window provides unobstructed view Reinforced polycarbonate construction Securely attaches to face shield for a tight seal Their rugged motors are explosion proof and rain proof to ensure a long life of dependability Heavy duty cast iron construction Carbon vanes and ceramic carbon seals reduce wear and repair expense Integral check valve with pressure relief on outlet side reduces pressure drop and improves vertical lift Self priming