JL Audio Mounting Adaptor Plate f/MediaMaster MM105/M100s - MMP-1-BK [010-13855-00]Mounting Adaptor Plate for MediaMaster MM105 M100s MMP 1 BK The MMP 1 BK mounting adaptor plate allows you to install a MediaMaster MM105 or MM100s into existing source unit openings that are larger than required (up to 8. 17 x 3 inch 208 x 80 mm). Constructed from a single piece of marine grade, machined aluminum, the MMP 1 BK provides a solid surface to mount your MediaMaster in locations previously occupied by other marine manufacturers source