At Supreme Timber we offer a choice of either grooved or flat clapping in both tanatone brown and tanalised green (natural) pressure treated to prevent water penetrating into the grain of the fence boards increasing the lifespan of the fencing structure. By using such capping it also provides extra stability to the fence boards while maintaining a snug fit resulting in a decorative finishing touch to the fence. The grooved capping comes in 4.2m lengths with a groove that slots over the top of the fence boards, tying a run of boards together. Usually nailed from the top down into the fence boards for a secure fit.