Type A & Type D: Can be used to measure the Rubber, Hard-resin, Glass, Thermoplastic plastics, Printing plates ... values. Battery: 1.5V battery Type A & Type D: Can be used to measure the Rubber, Hard-resin, Glass, Thermoplastic plastics, Printing ... plates, Fiber, etc. Type C: Can be used to measure the Hardness of Foam, Sponge, Shoes with incorporates material ...