PurCool Strips are powerful, economical, preventive maintenance for A/C condensate drain pans. Just place them anywhere in the drain pan where the PurCool Strips will contact the condensate water and enjoy up to six months of economical protection. PurCool Strips will adhere to the drain pan and will not float or move. They dissolve completely, leaving no residue. Safe for metal and plastic drain pans. PurCool Strips keep A/C and refrigeration condensate drain pans clean and free flowing. Use PurCool Strips to prevent condensate drain clogs, costly overflow, and corrosion.