Features: Touch-screen, long press to open/close, bring you good experience. S7 waterproof, 12-hour and 24-hour switching, the maximum-timer time 999 seconds. 4 in 1 multifunctional meter, come with timer, time, air OR water temperature meter, voltage meter. Small and compact, unique appearance, easy operation. High quality material, never flash, waterproof, high accuracy. High water temperature/low voltage alarm. The default low voltage alarm value 11.5v, and the default high temperature alarm value 75 , which can be self set. Specifications: Material: PC Voltage: 9-24V Dia: Approx. 4.7cm/1.85in Type: Air Temperature/Water Temperature(Optional) Note: The water temperature type needs to be connected with a special water temperature sensor. Red wire connected to the positive pole, the white wire connected to the negative pole, and the blue wire connected to the electric door lock. Package includes: 1 Set Thermometer Voltmeter