Heavy Duty Vise, Jaw Width 6 1/2 Inches, Maximum Opening 6 1/2 Inches, Throat Depth 4 Inches, Pipe Capacity 1/4 to 3 1/2 Inches, With Pipe Jaw RestrictionsNote: For replacement jaws and magnetic caps, see DrillSpot.com . Bench VisesHeavy-DutyReplaceable steel jaws are reversible: 1 side serrated, 1 side smooth. Full 360 serrated swivel lock base has 2 locknuts (except 3FDJ3 and 3FDJ1). Units have steel jaws, a ductile alloy body with large, ground anvil and serrated jaws. Pipe jaws are replaceable.