Cement coated shafts are used when resistance to withdrawal is desired. Sharp pointed nails have good holding strength but can split some wood types, in which case a blunt end is used which promoted punching instead. In a structural situation where force must be transferred through the fasteners successfully, the connection must be adequate based on connection length, diameter of the nails, and wood material type/strength being utilized. Generally nails in the US are measured by ‘pennies’ which is abbreviated simply ‘d’ and is thought to be a throwback to the old pricetag of certain boxes of 100 nails. Despite their size difference, common nails, box nails, and finish nails are all measured by the penny or ‘d’ connotation. Nails are most commonly furnished ‘bright’ which are plain, uncoated steel bu they are also available in aluminum, copper, brass, zinc, and stainless steel. If exposed to weather nails should be corrosion resistant (hot-dip galvanized, aluminum, and zinc-coated). Zinc-coated, while resistant to moisture, really are not suitable for exterior use. Corrosion resistant nails are most important on exterior siding, trim, and decks, etc.