Antique White Single Mount and Backing (20x16 for A3 print)

Single Antique White coloured mount with board backing. Mount size 20x16", Aperture size A3 (297x420mm) 

All aperture sizes (image sizes/holes) are cut 3mm smaller on each side, to accommodate the picture/print. For example. The 20”x16” mount, with an aperture of A3 (297mmx420mm) has an actual aperture size of 15.75”x11.75”.