Round head nails are mostly used for rough carpentry where appearance is not important. Round head nails are used when strength is essential. Round head nails are available in bright finish or galvanised. Galvanised are mainly used if the nail will be exposed to the outdoor elements. In this section we have a good range of Round Head Nails in 500grm and 1kg bags. Round head nails size list below, the longer the nail the thicker the diameter. Diameter x Length 2.00 x 25mm 2.65 x 40mm 2.65 x 50mm 3.35 x 65mm 3.75 x 75mm 4.50 x 100mm 5.60 x 125mm 6.00 x 150mm