301 Wilton Pow-R-Arm. This one is over 30 years old and has worn out a couple of 4" vises. I did break the little handle that locks it but replaced it with a grad 8 bolt.
Having a vise on a pivot like this is invaluable. Also eliminates the need for a pivoting vice jaw I guess. I have never had one.
I have another one I need to get a vise mounted on. Put them on the corner of the bench so I can work around it easier. Use the green or Blue now I guess, plastic lined jaws from Brownell's the ones in use here are also 30 years or more old. Pretty beat but still work and are soft enough for wood. I bought a new set 3-4 years ago for another vise the plywood and leather ones wore out.
Best vise I own is a 6" made in England vise I got from the Coast to Coast when I was about 18.
Dan