Enviro-Safe ProDry contains a dehydrating agent that converts system moisture into oil. We recommend the use of ProDry XL4 before the use of Enviro-Safe ProSeal XL4 to ensure all moisture has been removed from the air conditioning system.
Should be used on any home A/C system that has leaked below 15 psi (running or not running) or if the system has ever leaked below 15 psi in the past.  If you do not wish to use Pro Dry XL4, the system must be vacuumed prior to installing ProSeal XL4.
When put into an A/C system that has moisture or air, Pro Dry XL4 mixes with the moisture and air in system forming a synthetic oil which then mixes with the oil in the system.
DO NOT use in ammonia systems
DO NOT use in CO2 systems
DO NOT use in R410a systems- Pressure is too high and will explode the can- You MUST use the Enviro-Safe Proseal XL4 Direct Inject line of products.
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