What if, on a small keelboat or on a racing dinghy, the crew members wore Camelbaks when hiking out? The biggest ones hold about three liters, and they''re definitely small enough to fit under a large PFD. If the 3 liter Camelbak is full, that means that each person has gained around six pounds. If you have five people doing that, then there''s thirty extra pounds on the windward rail! If anybody asks any questions, the exscue can be that it''s easier for the crew to drink water with Camelbaks.