A reusable, double sided 3D printed version of the common marker stickers. 

The model is 10mm outer diameter with a 5mm diameter inner dot, 1mm tall.

Simple to scale diameter and height. The original 1mm tall Marker Coins can be tricky to pick up, scaling Z 1.6x to 1.6mm height make them easy to handle. 
Some scanners may benefit from larger or smaller Marker Coin diameters.

Benefits from Multimaterial printing! The inner circle on both side is a separate surface that can easily be assigned a color (white).