Made like the very oldest of Telecaster pickguards, these pickguards are made out of bakelite plastic instead of the more modern alternatives that are typically made from ABS. These are single ply with a straight edge, as opposed to having a bevelled edge exposing triple striped layers (typically white sandwiched between two black layers for a black pickguard).
Bakelite was replaced due to it's inclination to become brittle and break as it got old, but for the vintage enthusiasts, it's a must due to the way it looks as it ages and wears. 5 screw mount as per vintage specs, 2mm thick.