What is the "doubler" the Tybee guys were talking about. If I do some distance races uni, like RTI, some help with the spin would be useful.

I'm considering an extra set of port hole covers, drilled and tapped to allow a drinking tube to 1 gallon water bottles.

equipment list: vhf, gps, cell phone, food, anchor/rode, lights, safety tether. . .


Anything else you guys can think of?