A flat sheet (100) of corrugated paper for producing a packing, which has a symmetrical shape and comprises
- (a) two parallel spaced apart central creases (A) extending longitudinally from one edge (30) of said sheet to an opposed edge (31) thereof,
- (b) a central, first wall member (10) defined by a first transverse crease (I) extending from one to the other of said spaced apart central creases (A), by two angled creases (25) extending outwardly from said central creases (A) in symmetrical inclined directions, and by a first cut (15) generally having the shape of the letter I,
- (c) a central, second wall member (11) defined by said first cut (15), by two angled creases (25) extending outwardly from said central creases (A) in symmetrical inclined directions, and by an opening (16), said second wall member (11) having a central recess (27), and said first and second wall members (10 and 11) forming together an octagonal shape,
- (d) a central, third wall member (12) defined by said opening (16), by two angled creases (25) extending outwardly from said central creases (A) in symmetrical inclined directions, and by a slit (19) extending from one to the other of said spaced apart central creases (A), said third wall member (12) having a central recess (27),
- (e) a central, fourth wall member (13) defined by said slit (19), by two angled creases (25) extending outwardly from said central creases (A) in symmetrical inclined directions, and by a second cut (15) generally having the shape of the letter I, said fourth wall member (13) having a central recess (27),
- (f) a central, fifth wall member (14) defined by said second cut (15), by two angled creases (25) extending outwardly from said central creases (A) in symmetrical inclined directions and by a second transverse crease (I) extending from one to the other of said two central creases (A), said fourth and fifth wall members and (13 and 14) forming together an octagonal shape,
- (g) each of said angled creases (25) making an angle of 45 degrees with respect to said central creases (A),
- (h) two first end sections (1), one of which is defined by an upper edge (30), by portions of the two spaced apart central creases (A), and by said first transverse crease (I), and the other end section (1) being defined by said second transverse crease (I), by portions of said central creases (A) and by a lower edge (31),
- (i) two outer side sections (2) each located adjacent and laterally outwardly from a longitudinal center line of the flat sheet with respect to one of said two spaced apart central creases (A),
- (j) two top sections (3), each located adjacent and laterally outwardly with respect to one of said outer side sections (2),
- (k) two inner side sections (5), each being partly surrounded by portions of one of said top sections (3),
- (l) two bottom sections (6), each located laterally outwardly with respect to one of said inner side sections (5) and separated therefrom by a third crease (D),
- (m) two pairs of second end sections (20) each pair being attached to longitudinal ends of one of said top sections,
- (n) a first crease (B) extending between said upper and lower edges (30 and 31) to divide each said outer side section (2) from its adjacent top section (3),
- (o) two second creases (C) extending between two points spaced inwardly a short distance from said upper and lower edges (30 and 31), each second crease (C) separating one of said top sections (3) from one of said inner side sections (5),
- (p) two pairs of opposed short creases (32), each short crease extending inwardly from one of said upper and lower edges (30 and 31) respectively for short distances to thereby divide each of the top sections (3) from its adjacent second end section (20), and
- (q) two pairs of opposed transverse slits (21) spaced inwardly short distances from said upper and lower edges (30 and 31) and each pair connecting with the respective opposed ends of each second crease (C), separating said opposed short creases (32) from the adjacent third crease (D), and also separating each pair of second end sections (20) from the adjacent bottom section (6).