Large spring probably
Was wondering about gas but possibly would damp it. The spring chamber looks quite large and the ones kids used to use were quite narrow and had limits to prevent it bouncing too high. The travel on the rod attached to the spring appears to be quite a bit.
(, Wed 8 Jun 2016, 23:53, Share, Reply)
Gas ram:
www.vat19.com/item/v4-pro-10-foot-pogo-stick
and not cheap!
(
Varmint, Thu 9 Jun 2016, 8:26,
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