Simple but exactly fitting and excellent working inserts for IKEA 365+ coasters made of cork. Unfortunately, these get dirty quickly, because some liquid constantly runs down from the glasses. The inserts catch that and are easy to clean.

Print them in different colors and no one will accidentally drink from your beer anymore :)

These coasters are sold with 9cm and 10cm diameter. Both versions are  included in the STL-File.
Prints in PETG are certainly more suitable than PLA for hot drinks. I used PETG 0,2mm layer 20% infill.

Have fun!