First look the shipping box was in NOT THAT GOOD a condition BUT thankfully there was a second box inside which contained the mobile base, which was in EVEN Worse condition, but after taking pictures (JUST IN CASE) it appeared that all parts were there. I first looked for instructions. There were NONE! So, I just looked at the pics online and started assembly. There are two sets of straight tubes (a long set and a shorter set), a bag of hardware, two swivel Casters, two corner brackets each with a wheel, two corner brackets each with a bracket to mount the casters to and a bag with two red levers to raise and lower the base after it is moved to lock it in place. First take the two short tubes and place one between each of the two corner brackets that have the wheels attached and measure how wide you need it for your machine and then screw the bolts into the holes that line up with the threaded holes in the tubes and snug it up but do not tighten yet. Now do the same with the short tube and the corner brackets that have the mounting flanges for the swivel casters. Now take the two long tubs and insert each end into the openings in the corner brackets and measure again to make sure that the mobile base is the size needed for your intended machine. Keep in mind that the finished opening can be a little bigger BUT not smaller than the needed size of your machine. After you verify the size is acceptable then go back and tighten all the bolts. Now take the two red levers and next to the swivel caster mounts there is a spring-loaded foot that has an opening at the end with two holes opposite each other. Insert one of the red levers into each of the openings and insert one of the long hex bolts into the holes and then place a nut on the end of the bolt and tighten. Do the same with the other red lever. The only part left is to take eight 1-inch-long hex bolts and nuts and mount each of the swivel casters to the corner brackets and tighten. The mobile base welds are nice, heavy clean and straight. The base when complete is not light (about 50 lbs.) And I believe would be good for any machine up to maybe 1000 lbs. mostly due to the quality of the casters which are not garbage but also not the best. All in all, It appears to be well built and hopefully will last.