I got this from a guy couple years ago. Could someone tell me what it is,asls I think I so a pic of a one being used as an anvil stand it fit the anvil perfect it was in the gallary on this forum. What I would like to do is. Weld a piece of mild flat steel on to put my russion anvil on it. I asking because if it worth some money to someone i do not want to ruin it. Any help would be great.

Looks like it could be part of a machine's base, but irrespective of that, rather than weld a piece to it, I would go for bolting the plate to it, either use the existing holes, or drill and tap, use countersunk headed bolts (allen key type would be best) then if you want to adapt it, or return to its original state you can easily do so.,

If the surface is uneven make a leather or rubber gasket for it or bed the plate down on mastic

Also, it looks like a casting, cast iron to steel does not weld well easily

Good luck with the project whatever you decide