The 20mm Deck Jak Spacer clips snugly beneath the Deck Jak or Joist Jak pedestals and is stackable, providing an additional 20mm lift each. The 110mm diameter base provides a very solid platform.
DJ 20 Spacerhttps://www.urbanbuildingproducts.com/shop/Deck+Jaks/Deck+Jak+Components/Deck+Jak+20mm+Spacer.html