The car bumper bar 10mm regrind is then sent to a processor to pelletise. Here the flake is put through a water bath which washes the plastics and filters out further contamination through a method called sink float. The specific gravity of PP is 0.9 meaning it will float. Dirt, metal, ABS contamination will sink. The flake is then dried. The clean flake is then run through a pelletising machine where it is heated, extruded, and cut into small pellets and bagged into one tonne bulk bags.