Master carton

The standard hierarchy runs unit → inner pack → master carton. The unit is what the customer buys; the inner pack groups a few units for shelf or e-commerce picking; the master carton is the box that actually ships and stacks on pallets. Case pack quantity is how many units one master carton holds.

Master carton dimensions quietly determine freight economics: they set how many cartons fit a pallet layer, whether the pallet hits height limits, dimensional weight for parcel shipping, and CBM for ocean. Choosing a master carton that tiles a 48×40 pallet cleanly — and doesn't cube out at half-full — is one of the cheapest supply-chain optimizations that exists.