Features: Provide secure, air tight connection between propane Tanks. Monitors fuels level without removing Tanks. Color coded dials for allowing you to see at a glance when your propane level is low. This propane Tanks gas gauge can be worked with propane Tanks cylinders, propane regulator with hose and propane adapter. No tool required and easy to install with handheel grip for tightening. Great for using gas grill, heater, smoker, camp stove, lantern, table top grill, fire pit table, turkey fryers and more propane appliances. Specifications: Materials: Brass and Plastic Size: about 49x92mm/1.93x3.62inch Interfaces diameter: about 33mm/1.3inch Package Includes: 2Pcs Propane Tanks Gauge Level Indicator note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.