Abstract: A spine for a troffer light fixture is provided. The spine is configured to receive omni-directional LED bulbs. The spine comprises: a base, a first wall, a second wall, and first end walls defining a light chamber shaped as a trough. Interior angles between the first wall, second wall, and base is 90-100 degrees respectively. The second wall defines a plurality of apertures each having a central axis arranged generally parallel in a linear arrangement. The apertures include: a pair of flanking apertures, the axis of each flanking aperture positioned 80-110 mm from one of the first end walls, and at least one interior aperture, the axis of each interior aperture positioned 135-145 mm from the axis of an adjacent aperture. Each of the plurality of apertures provides an opening through which an omni-directional LED bulb can extend parallel to the base to engage a socket mounted on the spine.