XCEL 6.5mm ThermoBamboo Dive Boots with Zipper6 5mm XCEL ThermoBamboo Dive Boots w Zipper The XCEL ThermoBamboo dive boots feature 100% stretch neoprene, a poly fleece lining for heat retention, and sealed seams to keep cold water out. Convenient side zipper is also sealed to eliminate flushing. Puncture resistant sole. 90 Day Warranty Sizing Tip: Choose your regular USA shoe size and round down if you're a half size. Example: Men's 9. 5 should choose size 9 Thickness Chart: *Water temperatures