A 140 × 25 mm solid straight-grain WPC decking board, co-extruded in one piece from wood-plastic composite, weighing a solid 4.292 kg per metre — and that heft is the most convincing quality proof there is: a core densityA 140 × 25 mm solid straight-grain WPC decking board, co-extruded in one piece from wood-plastic composite, weighing a solid 4.292 kg per metre — and that heft is the most convincing quality proof there is: a core density of around 1.23 g/cm³, squarely in the high-density band the industry recognises, solid throughout and tightly packed, so one heft of a board tells you the material is all there. First, at 4.292 kg/m the board weighs more than a hollow profile and costs more to freight — but the strength, screw-holding and wind stability it buys are well worth it on ground-level gardens, patios and platforms; for load-limited roofs and balconies, the lighter 140 × 20 solid board (3.35 kg/m, same formulation) is the better call. The 140 × 25 solid straight-grain board is the weight-anchored workhorse of the solid range: full density, full strength, a modern face — the dependable pick for premium residential and light-commercial installations.