Container

A container formed from a flexible sheet of resilient thermoplastic resin and having a body section and a cover section hinged together by a hinge integral with both sections, each section having a closure wall with side and end walls of a size to telescope one into the other when the sections are in closed relation, said side and end walls meeting in angular relation to form corners, all of said corners of the inner telescoping walls being undercut in a plane at an angle to both meeting walls on their outer surfaces and all of said corners of the outer telescoping walls being undercut in a plane at an angle to both meeting walls on the inner surfaces whereby the undercut corners of the sections will lock at all of the corners when the body and cover sections are in closed position.