The sliding panel (1) comprise on at least one of sides thereof in the direction of the movement thereof, the reinforcing member (4) consisting of two aluminum sections (4a and 4b) connected by a polyamide thermal break (4c) and having two edges (4d and 4e) that define the longitudinal groove (22) having the same width from one end of the member (4) to the other end thereof. The guides (10) and the longitudinal inverted channel section (11) are placed in stationary positions on the benches (8 and 9) belonging to the profile sections of the frame (2) of the sliding window or sliding glass door. Each guide (10) comprises, in the center of the block (12), the vertical rod (20) having, on the top end thereof, ball bearings (21) that are located exactly between the edges (4d and 4e) and are located in the longitudinal channel (22) through which the panel (1) is guided in the movements thereof.