Related Clues:

• Hold stuff
• Room on a ship
• Cargo weight
• Shipping figure
• Shipping measure
• Merchant ship's cargo
• Freighter's capacity
• Cargo area
• Merchant ship capacity
• Ship's carrying capacity
• Shipping weight allowance
• Weight of a sort
• Cargo area on board
• The 21 across of the horse, or the ship - in the sound of it
• It's for a ship, and that's about the size of it