Retractable base structure
The interlocking fish-scale structure extends from 4 inches up to 15.8 inches across seven set heights. You twist the base to release the lock, pull to the height you need, and twist back to set the ring in place.

We built this retractable base to adjust through seven height steps, matching standard home seat height at its full extension. The top carries a soft PU cushion that stays comfortable in cold or warm weather. It packs down flat and travels with two rolls of custom drawstring bags.
$57.94Catalogue price from the last rebuild; the live listing has the final word.
The interlocking fish-scale structure extends from 4 inches up to 15.8 inches across seven set heights. You twist the base to release the lock, pull to the height you need, and twist back to set the ring in place.
A PU cushion rests over the top ring to soften the seat. It avoids the cold shock of bare hard plastic on freezing mornings and does not hold heat after hours in the back of the car.
The set includes two rolls of 20 bags, giving you 40 liners total. Each bag is made from 1.6 mil thick LDPE plastic, fitted with drawstrings that pull tight so you can lift and knot the bag cleanly.
When twisted fully down, the entire unit compresses into a 4 in high disc. It slides under a bench seat or behind vehicle cargo bins along with both rolls of spare bags.
Pieces that ride along in the same trunk or pair with this one at camp.
$57.94