Structural blind rivets offer the highest shear and tensile strength of all rivets and feature and internal locking feature so that the rivet will not loosen over time. These are generally used on truck bodies as they have a high pull-out strength and are leak resistant. This particular one features a countersunk head, made so sit flush with the surface in a countersunk hole. Grip range is the amount of material the rivet will be going through, not the actual length of the rivet ,which will always be longer than the grip range.