Abstract: A backpack includes a frame system. The frame system has two L-shaped members, one or more cross bars, and an attachment bar. A pack has a base, a rear wall, a front wall, two side walls, and a closable lid. The pack also has shoulder straps disposed at the rear wall and a pair of elongated channels on the rear wall. The pack removably couples to the frame system by inserting a long leg of each of the L-shaped members into the respective elongated channel. When the pack is coupled to the frame, the base of the pack is supported on two short legs of the L-shaped members, the frame system is on an exterior of the pack, and the attachment bar can removably couple to either end of the two L-shaped members. An insert is sized and shaped to be removably inserted within an interior volume of the pack.