The Fernox Leak Sealer – External 50g (LSX 61016) is a high-performance solution for sealing leaks in plumbing and heating systems. Designed for quick, external application, it provides a durable and reliable seal without the need to drain the system. Ideal for professional plumbers and DIY users, this leak sealer ensures efficient repair and long-lasting protection. Shop Plumbco for trusted Fernox products with fast delivery.