Because the float article talked about 550lb to 600lb max for the floats I "assumed" that the 275lbs marked on the float drawings water line was for each float, some arithmetic has revealed that, that is not the case. The 275lb @ waterline includes both floats or about 137.5lbs floatation for each float at the waterline shown. The good news is that the floats if watertight should keep a little over 600lbs from sinking albeit most likely in an inverted position. My math is based on a cubic foot of water weighing 62.4lbs.