Related Clues:

• They're short in the U.S. and long in the U.K
• Theory of natural selection, for starters, is for heavyweights
• Generous allowance to the Poles
• Heavyweights in abundance
• Loads (sl.)
• 4,000 pounds, for two
• 6,000 pounds, for three
• Heaviest units I can think of
• Five fifths
• A heck of a lot
• "16 ___" Tom Jones
• Heaps of CDs
• "Sixteen ___" Tom Jones
• Clash's '80 outing The 16 ___ Tour
• Cargo weight units