O'Neill Wetsuits - O'Neill Psychotech 6/4mm Internal Split Toe Wetsuit Boots - Black :: Men > Wetsuits. Men's wetsuit bootsThickness: 6/4mmTechnobutter 2 neoprene: Extremely light with unparalleled flex and warmthSingle fluid seam weld: Non-chafing high-grade. silicone-based urethane\n that prevents water entering the bootClosure: Pull-on entrance with velcro straps securing the boot to your\n feetTechnobutter 2-air firewall lining: Identical features to TechnoButter\n with the addition of air technology Size: UK 5,UK 6,UK 7,UK 9,UK 10,UK 12.