30 a through the first aperture 40 and the second sub aperture 58 a over the portion of the first major surface 54 defined by the bridge 59 through the second aperture 58 between the plateau 66 and the edge 42 and around a back edge 68 of the sliding plate 50 the web 120 then extends to a handle 122 at an end of the web 120 that is distal with respect to the ring 118 to cinch down the shoulder straps 1 16 a 1 16 b the handle 122 is pulled in the direction indicated with arrow c an advantage of the present invention is that pulling the handle 122 displaces the sliding plate 50 with respect to the mounting plate 30 in the direction indicated with arrow b thereby separating the plateau 66 from the edge 42 thus the web adjuster 10 automatically releases the web 120 when tightening the harness 110 conversely if there is an attempt to release the cinched down shoulder straps 116 a 116 b i e by pulling the web 120 in the direction indicated with arrow d the plateau 66 and the edge 42 increase the grip on the web 120 in proportion to the force attempting to release the should straps 116 a 116 b thus a child 39 s attempts to remove the shoulder straps 116 a 116 b are prevented similarly the web 120 also remains.