These durable, non-toxic thermometers measure from -30C to 120C and from -22F to 240F. Safe to use, these thermometers are made from plastic and are mercury-free. Use them for measuring the boiling points of various liquids. Set of 10 thermometers in a reusable storage box. Ideal for grades 3 +. Each thermometer is 175mm tall and 23mm wide.