This generously sized coaster is designed to help protect the surface of your table or desk from hot drinks or the condensation from cold drinks. By sandwiching this coaster between layers of cork the 3D printed plastic component is not impacted by temperature extremes.
This coaster is designed to contain two properly sized corks or equivalent material disk inserts in its equally sized top and bottom cavities. These may be held in place with silicone glue and adhesion is enhanced by the underlying grid pattern. The cork disks should be approximately 3.875 inches in diameter with a thickness of 0.25 inches. Properly sized cork disk inserts may be acquired from the following source:
http://www.woodturnerscatalog.com/p/54/5252/Turners-Select-Cork-Coaster-Insert
Note that the cork inserts from this source will also be held in place due to the friction of a snug fit, but glue may be used if desired for a more secure fit. If the cork inserts are extremely tight you can lightly sand the edges to reduce the diameters of the corks before inserting them. If the fit is very tight the corks may bulge outwards after being inserted but I've found that compressing them between a flat table top and a heavy book will compress the corks after which they will fit well afterwards when not using any glue.