middle press portion 52 according to this embodiment the inner barrel member 401 of the locating barrel 4 has an opening 43 in the peripheral wall in line with the longitudinal slot 42 near the rear side the outer barrel member 402 has an opening 44 in the peripheral wall corresponding to the opening 43 of the inner barrel member 401 the middle press portion 52 of the resilient retaining rod 5 is insertable through the openings 43 and 44 to the outside of the locating barrel 4 further the back holder shell 122 of the base 12 has a small through hole 125 corresponding to the middle press portion 52 of the resilient retaining rod 5 the coupling barrel 3 has the front end thereof fixedly fastened to the display panel 11 between the front face panel 111 and the back cover 112 according to this embodiment the coupling barrel 3 has the front end terminating at a mounting plate 33 fixedly fastened to the front face panel 111 and the back cover 112 with screws 72 and the rear end terminating at engagement means 31 according to this embodiment the engagement means 31 comprises two protrusions 311 corresponding to the beveled notches 451 the coupling barrel 3 further has a longitudinal slot 32 corresponding to the longitudinal slot 42 of the inner barrel member 401 referring to fig3 u02dc 5 and fig1 and 2 again when wishing to affix the display panel 11 to the base 12 the coupling barrel 3 is sleeved onto the tubular body 41 of the.