A mounting rail for a firearm is described, wherein the rail includes at least one catch arranged on a flat upper surface of the rail. The at least one catch serves as a means of fixation for at least one accessory. The rail also includes a housing that extends longitudinally, and the housing is suited to receive a printed circuit board allowing for an electrical connection with the accessory. The housing is partially defined by at least one recess, each recess being arranged between two opposite flanks of the corresponding catch. A top of the corresponding catch extends transversely on either side of a median plane of the rail above the housing.