These Slip Joint VamPLIERS have the signature concave shaped jaws with vertical and horizontal serrations designed inside of the jaws. This which gives the perfect bite around a stripped/rusted/corroded screw, nut or bolt for extraction. Compared to its predecessor, these jaws are wider to tackle bigger problem screws. Adding to its big bite is the "slip-joint" feature made with reversed body structures that allows the jaws to adjust and firmly take on bigger screws, nuts, and bolts!