These hardwood pucks are made of Beechwood and suitable for replacements, or a new set, if you decide to build your own Sjoelbak. The pucks are 52mm in diameter and 13mm high. They fit a tournament sized Sjoelbak with slots that are 60mm x 17mm. Be aware that some sell pucks that are flat-faced, but Dutch Games Pucks are slightly concave on both sides for better sliding and control. They satisfy official Sjoelen Federation requirements and are made in the Netherlands.