Yes. It is long enough to fit the high walls. I used it on my HW256.
It has 4-5 holes along the supports to select different heights. You slide it down a bit when you slide the bunks out to give you clearance. The top "T" portion slides into the bottom portion which is a larger diam. You simply align the holes and slide the pin thru. Very simple.
It is made out of lightweight aluminum and does not rust. I used mine for 9 years and never had any problems.
I highly recommend it. It also has quick release clamps on the top "T".
Front tires go in the TV or pop up. I carried mine in the back of the SUV.