TKN-4S…Plain Steel Trunk Nails 4 Ounce Lot, approximately 90 nails. Steel nail is 1-1/4 inch long. Trunk nails are driven in to attach hinges, corners, locks, etc. They are then bent over inside the trunk, which helps prevent the hardware from being pulled off. This why trunk have paper coverings inside to hide the bent over nails. Trunks have been constructed in this manner for hundreds of years.