to one another as the panels 7 and 9 are folded along fold line 11 the interfitting notches 33a 33b and tabs 35a 35b constituting gap 31 between panels 15 and 23 interfit with one another as shown in fig1 thus at least in part interlocking the inner edges of panels 15 and 23 as indicated by the arrow in fig1 the first end panel 13 is folded along its respective fold line 17 so that its inner edge is disposed along fold line 25 between panels 21 and 9 then the third outer panel 21 is folded upwardly along its fold line 25 so as to be in face to face relation with the previously folded panel 13 as shown in fig1 lastly tab 39 is folded along its fold line 43 so as to be received in notch 45 thus positively holding panels 13 and 21 in face to face relation it will thus be appreciated that by the use of fastening means 37 i e tab 39 being received in notch 45 and due to the interfitting tabs and notches constituting gap 31 corner protector 1 is positively held in its three dimensional assembled shape without the requirement of external fasteners adhesives or the like further because of the heavy duty construction of corner protector 1 of triple wall corrugated material or other suitable board like stock the corner protector 1 of the present invention will successfully withstand high impact loads such as may be applied to the corner protector by the article being shipped during transit because of the higher load carrying capability of the corner protectors 1 of the.