Lifter Boot - An off the shelf option.
Retail rubber boot (
Bubble Lifter )
Part # 9744K13
Phone (330) 995-5500
It has a 1 13/16"
I.D. at the top and a 3'' I.D. at the bottom. O.D.at the bottom
is 4 1/2.
This boot will extend to 8'' and is 2'' when collapsed.
It has 9 ribs.
While not an exact match
to the Robot's original, it is very close.