Postsaver fence posts are protected with dual-layer groundline barrier sleeves to prevent ground rot., they are used all over the world and have been in production since 1994. They are independently tested and proven to dramatically extend the lifespan of wooden fence and gate posts. On the inside is a thermoplastic bitumen layer that melts and penetrates into your post generating an air & watertight seal. The second layer is an ultra-strong thermoplastic skin that shrinks down tightly around the post giving a second layer of protection. Don’t let your new and expensive fence posts rot through at ground level after only a few years. Postsaver is used extensively by Network Rail, Western Power, Highways England, Forestry Commission, Environment Agency, and hundreds of Sawmills and fencing outlets across the country. Size: 120cm H x 4cm W x 4cm D