Air Conditioner Fin Guard protects your RV A/C unit's delicate evaporator fins from damage by tree branches, hail, or accidental bumping by anyone working on your roof. Your air conditioner's fin and coil assembly will lose efficiency if the the fins are bent or crushed, and if the coils are punctured they will require expensive servicing. That's why older A/C units with openings at the back of the shroud need protection, and Leisure Time Products Fin and Coil Shield gives complete protection.