Patent ID: 7708185

Claim:
A plastic box formed of a plastic that closes a square opening by bending inner flaps, arranged on one pair of opposite two sides at a periphery of said square opening, towards an inside of the opening, and folding an outer flap, comprising an insertion flap piece and arranged on one side of an other pair of opposite two sides, while inserting and latching said insertion flap piece into the inside of said opening between an other side of said other pair of opposite two sides and the bent inner flap, the plastic box comprising: a lock mechanism to engage respective base end parts of said inner flaps to notches formed on respective end parts of a bend line bent from said outer flap of said insertion flap piece and the notches formed on the respective end parts of the bend line extend further outward from the outer flap than the bend line; and a finger-receiving brim piece protruding from said bend line towards an outside of the opening is provided at a position shifted from a center of said bend line towards a side edge.