Tessellated Octagonal Coaster

Has interior octagons tessellated intended to leave an air gap for condensation so glasses don't stick to the coaster. Coasters are 100mm wide which should fit most normal-large size glasses and mugs. Inspired by other coasters with a hexagon shaped coaster. I needed a shape that worked on a side table with limited space so an octagon allowed for tiling coasters next to each other without being the wrong angle. Customizable with OpenSCAD.