The construction of the puppets was revolutionised for the Thunderbirds team by the development of bondaglass, a fibreglass cloth and polyester resin, similar to that used to make custom car bodies. Heads are first made in plasticine, then moulded in glass fibre. Moving lips and eyes are added and then the crowning glory - the hair in the latest styles. Each main character has up to five heads with different expressions to suit the mood. The rest of the puppet is made in a plastic and is in the perfect proportion of one third human stature with the hands and feet to suit the fitting. Any character can be made up from these interchangeable components. Each dressed puppet cost between 250 and 300 pounds.