Most beverage bottles are produced from polyethylene terephthalate (PET), which is transparent and light. Detergent and household good bottles are primarily produced from high-density polyethylene (HDPE), which is a stronger material and not transparent. HDPE bottles are produced using a blow-molding process that involves feeding blended HDPE resin pellets and colorants into an extrusion machine and using heat and pressure to form the resin into a round hollow tube of molten plastic called “parison”. The parison is captured by bottle molds and is mounted radially on a wheel as it leaves the extruder. Once inside the mold, air pressure blows the parison into the bottle shape of the mold. The mold is rapidly cooled and removed, producing a bottle.