I had the idea this 6" vise was 14" long- it is 16.25" long. That's ok, I made room. The quality in machining was much better than I expected. You'll notice in the pics, you can't even see the seam in the jaws with the vise closed. I tested the jaws and the best I could get was an accuracy of .0015". Horizontally, it was dead on at .0005". They didn't use the stronger acme thread on these vises. It has a more fine deep thread I don't recognize, which is good for torgue, but not as strong as an acme thread. I did bear down on clamping with no bad effects and the vise held the part very well and I was confident with it. The screw has exposed threads with the vise opened over 4.5", so I made a metal plate to cover the screw to help keep chips out and the threads clean. (See pic). The total jaw opening is 6-3/8". The total jaw width is 6-3/8". The Jaw height is 1.75". The base is over 8" wide and 16.25" long. From the bottom of the base to the bottom of the jaws is 2-7/8". Even for it's size on my mill, it will function just fine for certain jobs, but I'm ordering the 4" vise for better reach on smaller work, as my 3" vise is too limited for what i do. I made a spin handle for it, but it operates very smoothly even by turning with the fingers. I am satisfied. A well made vise for the price. It weighs over 50 lbs.