Wall cabinets and fiber management trays are provided. A cabinet includes a mounting panel, the mounting panel including a rear panel and a mounting bracket extending from the rear panel along a transverse axis. The cabinet further includes a backboard mountable to the mounting panel such that a gap is defined between the backboard and the rear panel along the transverse axis. The backboard includes a main body defining a first cable manifold and a second cable manifold each extending along a longitudinal axis and a splice section positioned between the first cable manifold and the second cable manifold along a lateral axis. The cabinet further includes a plurality of splice trays disposed in the splice section.