HE TRUMA LEVEL CONTROL USES ULTRASOUND TO ACCURATELY DISPLAY HOW MUCH GAS THERE IS IN A CYLINDER. THE LEVEL CONTROL ALSO INDICATES HOW LONG THE GAS WILL LAST. THE LEVEL SENSOR SENDS THE CALCULATED DATA TO YOUR INET BOX. WITH THE TRUMPA APP YOU CAN THEN PROCEED TO CHEK THE MEASURED DATA ON YOUR SMART PHONE OR TABLET. WITH THE TRUMA LEVEL CONTROL ITS EASY TO ALWAYS HAVE YOUR GAS SUPPLY UNDER CONTROL. NOT SUITABLE FOR PLASTIC GAS CYLINDERS, REFILLABLE GAS CYLINDERS GAS TANKS OR BUTANE CYLINDERS.