Fernox F4 Leak Sealer 500ml

Seal small, inaccessible leaks and weeps in a central heating system with fernox f4 leak sealer. There is no need to drain down the system before use, and once dispersed, it will be effective 1 to 24 hours after application.

Seal small, inaccessible leaks and weeps in a central heating system with fernox f4 leak sealer. There is no need to drain down the system