Abstract: The self contained light unit is for use with a fishing tackle box having a movable tray assembly. The light unit consists of a thin, rectalinear housing having flat top and bottom portions and opposing side portions. The bottom portion has a transparent sheet structure and a lip for slidably receiving it. The housing further has a reflective sheet portion disposed therein and at least one light source located between the reflective sheet and transparent sheet for illuminating predetermined portions of the tackle box. A power source is placed within the housing, and the housing has access to the power source. A switch is located outside the housing, and hinges are attached to the opposing side portions of the housing and to the sides of the tray unit. The hinges are constructed to provide a predetermined angular placement of the light unit as it is opened so that the light source is directed to predetermined portions of the tackle box to aid the fisherman in locating the tackle therein.