Hex bolts are the most common construction fastener having a hex head that can be secured with a socket or wrench and mated with a nut or other internally threaded item. Hex bolts are also reffered to as Hex Cap Screws, Tap Bolts, and Hex Cap Bolts.
Fully Threaded vs Partially Threaded Hex Bolts
Fully threaded hex bolts
Fully Threaded hex bolts are generally used with a tapped or threaded hole and screwed all the way down to the head. These are a great option when sideways force is not a concern.
Partially threaded hex bolts
Partially threaded hex bolts feature an unthreaded portion underneath the head that provides more holding power and greater strength from the sideways force since the unthreaded portion is much stronger than the threaded area.