EPA regulations require that whenever a refrigerant retrofit is performed (recharging or converting a refrigeration / AC / Heat Pump system to use a substitute refrigerant), the system must be properly marked. This R-438A conversion decal is to be affixed to the exterior of the system in the most visible locations so that any technician would easily see them. Multiple stickers are recommended in locations such as the primary servicing panel, the electrical disconnect, near the refrigerant access connections, inside the electrical panel, etc. On split systems place one at the air handler location as well. When used in combination with a Refrigerant Retrofit Report (see our other listings for this decal) this leaves a readily identifiable record for the next technician so they will know what alterations have been made and what they are working on. For a bulk purchase / large quantity wholesale discount please message us. Decal designs are Copyright 2023 RefrigerantStickers.com