This product is a combination of 2 Enviro-Safe products into 1 for maximum cooling performance. This will remove moisture in the A/C system. Moisture can cause corrosion in the A/C system or the A/C to freeze up. Please note, the top of this can has a 134a top which means you need a hose or gauge with the proper ends in order to install this product into your 1234yf vehicle. We have hoses and gauges available under these numbers: 3600 & 3610 gauges and 3635 & 3615 hoses. Please use the search bar at the bottom of the page or look in the "Gauge & Hoses" section of our site. The other part of the product will reduce friction in system and provide colder air duct temps in most cases. Compatible with any automotive refrigerant except ammonia and CO2 Drying agent Colder air Longer life A/C Booster DO NOT use in ammonia systems DO NOT use in CO2 systems Cannot be sent to Alaska or Hawaii or exported to foreign countries except in pallet quantities Gas propelled Installs the same way as refrigerant Cannot be added to a fully charged system