Yost MU-360 Plastic Jaws are designed to fit most 4" to 6" vise jaw. These universal jaws feature three high strength magnets (unlike other jaws that only feature two). The distance from the edges of the magnets is 3-3/4", allowing them to be used on a 4" vise up to a 6" vise. The plastic design prevents damage to your project. These jaws feature a prism (diamond) groove pattern. This design more effectively grips products than traditional horizontal grooves or standard smooth jaws.