If you purchased from Furuno USA, this mounting plate isn't used/needed. The cutout template you have in the box should end with "A" and matches an installation without the extra panel. Furuno USA determined that panel wasn't needed and the install looks neater. IF you are a Furuno USA customer and wish to use this additional panel (Using cutout template ending in "B"), you can contact our support and we can arrange for you to get one.