The Steroplast Sterochef Blue Detectable plaster is a hypo-allergenic visual and metal detectable plaster specifically designed for the food manufacturing and processing sector. Visually and Metal Detectable The Steroplast Sterocheck blue detectable finger extension plaster has multiple detectable attributes. The first being it 's vibrant blue colour which is the only colour that does not occur naturally in food making it easily visually detectable. The second feature is the ability to be detected where metal detection equipment is operational. The ultimate in high security.