The GasWatch TVL 212 is a propane-level indicator that allows you to know how much gas is left in the tank. The GasWatch TVL 212 features a built-in leak detector, a flow limiter in case of a major leak, and 100-percent use of the propane in the tank. It can be used with propane tanks of up to 40 pounds with a type-1 QCC connection, including those for boats, gas grills, RVs, propane heaters, turkey fryers, camping stoves, and all other outdoor propane appliances. Contact: (704) 814-0930 or www.gaswatch.com.