The ornamental design for a backrestplate, as shown and described.
A portion of the disclosure of this patent document contains material which is subject to copyright protection. This patent document may show and/or describe matter which is or may become trade dress of the owner. The copyright and trade dress owner has no objection to the facsimile reproduction by any one of the patent disclosure as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright and trade dress rights whatsoever.
The FIGURE is a front plan view of a backrest plate design.
The rear view of the backrest plate design is omitted as it is merely duplicative of the front plan view shown in the FIGURE.
The top, bottom and side views of the backrest plate design are omitted as these views are devoid of surface ornamentation.
The broken lines in the FIGURE are for illustrative purposes only and form no part of the claimed design.