U-shaped post supports are sized to the post section, most commonly 70×70, 90×90 and 100×100 mm, and many are width-adjustable within a range such as 71–161 mm. Choose a holder that matches your post so the timber sits snugly in the channel, then secure it with the side screw holes provided.

Yes, U-shaped post supports are typically made from hot-dip galvanised steel so they withstand rain, moisture and permanent outdoor use. The galvanised coating resists corrosion whether the support is bolted to a slab or set in concrete, making it durable for fences, decks and pergolas.

Choose a concrete-in U-shaped support when you are setting posts into a fresh concrete footing for maximum permanent strength, and a bolt-down version when fixing to an existing concrete slab, patio or paving. Concrete-in types have a long spike or tang that is buried, while bolt-down types have a flat plate with holes for anchor bolts.

A timber post is secured into a U-shaped support through the pre-drilled holes in the channel sides using coach screws or bolts, which clamp the post firmly on both faces. Fixings are not always supplied, so check the product details; the GeZu Impex range lists the post size and hole pattern for each U-shaped support.