The tank level alarm with a bright flashing LED and a loud beeper The tank alarm grabs attention with a bright flashing LED and a loud beeper when liquid level is too high or too low. Easy to install. Easy to adjust the depth in tank. Stop overfilled or empty tanks for good! Always on duty because it uses uninteruptible battery power. Loud warbling tone cuts through the loudest industrial noise. The tank alarm guards against overfilling or running empty. Easy to install as its battery powered. No wires, no electricians needed. Lithium battery included lasts for years. Uninterruptible battery power works through power failures, can't come unplugged, or be defeated. And, because the Tank Alarms don't use any power until alarming, the batteries last for years. Easy to adjust the depth of the Tank Alarms - just loosen the nut on the cord grip and slide the alarm to the correct depth. many mounting situation can be selected such as 2" NPT, bolt-on flange, bulkhead feedthrough etc. Float is protected inside a pipe with screens on all sides so solids, debris or insects can't ever foul the float. These have even been used on sewage tanks. Bottom screen is removable. Many different materials as the situation dictates: PVC, polypropylene, Nylon, Stainless steel. chemical resistance chart. Any Depth. Standard depths available up to 5 ft. Everything Included Every unit includes a threaded bushing to adapt the 1" NPT threads for the cord grip to 2" NPT. threads. Lithium battery or AC adapter is included. Rugged. Built for rough, wet and corrosive environments. A functional check is simple - just loosen the cord grip and lift the Tank Alarm out. Reliable float switch is completely screened-in to protect from debris in tank. Safe. 9 volt circuit in a waterproof No wetted metal parts. Uninterruptible battery power lasts for years. Lithium battery always included. Extremely long-lived batteries available. Choice of power. Battery or AC power option.