Aerosol 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. 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 It should be noted that these are 4oz cans.