High financial penalties imposed by supermarket chains when goods are faulty make it paramount that defects are kept to an absolute minimum.  ALS Controls faced a production line running 24 hours a day, 7 days a week manufacturing plastic milk bottles and injection moulded bottle caps. The 40mm diameter moulded caps are produced in three different colours to signify the type of milk; skimmed, semi-skimmed or full-cream.  It is important each cap is produced to the correct dimension and shape.