Marshall, for webbing I wear a belt I made form 1" tube. It has water knots on each end. Mine is doubled, then doubled back to a pair of caribiners, ie one through both knots, then another through the doubled middle and back, meeting the CBs in the middle. 15 feet wasn't enough for my 35" waist, x4 + knots. I know this because Neptune cut it wrong the first try. 15' would likely work for you.
(seven two 0)-298-2242