A container (10) for shipping products has opposed end walls (11, 12) and opposed side walls (13, 14), each having an inner wall panel (16, 17 and 20, 21, respectively) and an outer wall panel (18, 19 and 22, 23, respectively) defining double thickness walls. The outer wall panels in the side walls are disposed orthogonally to the outer wall panels in the end walls to define a rectangular or square outer container configuration, and extension panels (25a, 25b) on opposite side edges of a first pair (16, 17) of the inner wall panels extend diagonally across interior corners of the container to define with the inner wall panels an octagonal inner container configuration. Bottom flaps (40, 41, 42 and 43) foldably connected to the bottom edges of the outer wall panels form a peripheral bottom wall (15), and include quick-lock detents (46, 47 and 52, 53, 54) to enable quick and easy set up of the bottom. In one embodiment (10'), a reinforcing panel (61) is formed in two of the inner wall panels, and is foldable to a position between the inner and outer wall panels, at the top thereof, to reinforce the walls of the container. A blank (B, B') for making the container (10, 10') is also disclosed.