The well-known hard plastic chopping board
Can also be used as a cutting mat
Get a plastic chopping board in the size you want. Variety of thicknesses to choose from.
An excellent chopping board for cleaning fish, as the bones are easy to spot.
All chopping boards are sawn on a circular saw and have pointed corners. If you want round corners, it can easily be done with sand paper.
They are also suitable as cutting mats or painting underlay, as it is virtually impossible to get glue, varnish or paint to stick to the surface.