Large 8.8 inch jaw opening. Outside rail edges of the body are machined. Vise nut does not extend beyond the end of the vise body. D688 has the same footprint as the D675 vise. Distance from keyway to stationary same as D675. Groove Lock jaw (D60-315) and workstop (WSRL46) standard. Patented “O” ring pull down feature standard. Approximately a 20% increase in clamping pressure over D675 vise. Distinctive patented design of the “Kurt Look”. Patented AngLock design. Bed height matched to size 2.875" (73.025 mm) ±0.0005". Repeatability within 0.001". Sealed needle thrust bearing used at hex end of screw to reduce clamping friction. The original Kurt Anglock D-Series vises are designed for precision part clamping on basic machine tools such as knee-type mills, grinders and machining centers. D-Series vises are ideal for use in running production parts where datums, flatness and parallelism is important. You can precision bore, tap, drill, grind and finish with high accuracy on most parts made of die cast aluminum, steel, and iron in your Kurt Anglock vises. No other brand can give you the time proven accuracy of the Kurt Anglock vises. All Kurt vises have a friction reducing, needle bearing, thrust collar. The needle bearing increases jaw clamping pressure.