The ATB1, Type-K bead thermocouple is used to take temperatures of air, surfaces or liquids up to 400 deg F. Use the ATB1 for outdoor dry bulb temperatures when finding target superheat. The ATB1 can be used with any of our meters that measure temperature and any thermometer accepting a Type-K thermocouple. The wrap-tab allows the thermocouple wire to conveniently store on the plug. Just wrap the excess wire around the wrap-tab and feed it through one of the eyes. Keep a few of them set at different lengths for fast, job specific, switching between thermocouples. No more tangled messes in your tool bag.