Features: The innermost is the temperature: it corresponds to R134a, R1R2 and R22 air conditioning systems respectively. Fluorination pressure: -30~250Psi One end of the low-pressure connector is connection to the low-pressure maintenance valves of the air conditioner, and the other end of the bottle opener is connection to the refrigerants tanks. Open the valves of the refrigerants tanks, and then open the low-pressure valves to add fluorides. Using the adapter and hose in the kit, the refrigerants tanks can be directly connection to the air conditioning system and filled according to the correct step and quantities. Scope of application: DC12V-24V can be installed on vehicles, motorcycles, ATVs, SUVs, boats and other mean of transportation. Specifications: Component:Copper Package Includes: 1pcs A10176 Fluorides Meter 1pcs R134(bottles suitable for American standards, please check the size) 1pcs Low-pressure Self-locking Connector 1pcs Opening Valves 1pcs Refrigerants Bottle Opener 2pcs Air Conditioning Valves note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you donot mind befores you order. 2.Due to the differences between different monitors, the picture may not reflect the actual coloring of the item. Thanks for your understandings.