what are worksurface extension plates?

BullseyeBore Core Worksurface Extension Plates are an optional accessory in the BullseyeBore Core accessory ecosystem. 

A BullseyeBore Core Worksurface Extension Plate is a flat aluminum circular plate that can be either held in place or tacked in place on the flat worksurface to “extend” it so the worksurface patterns are fully visible. Worksurface Extension Plates “extend” a small worksurface so the Reference Pattern and at least one Alignment Pattern is visible.

The plates has a 6” diameter with the BullseyeBore logo on one side and nothing on the other.