If you don't need the piston, there is kit on the shopping sites with 3 rings that can fix to it to make it stationary. For max height you use all 3 rings, med 2rings, tall people or short desks 1 ring. It's a solution. I guess the PVC probably cheaper. I laugh at my office mate who stole my chair and went to a lot of trouble to do so, getting a cheap chair, now with fixed height. If I ever find it, I'll steal it back though.