Aqua Sphere Size Chart The Phantom is the only wetsuit with an adjustable fit, delivering power and comfort through its proprietary Core Power System. Paired with Aqua Sphere's unique Bio-Stretch Zone, this suit gives you unparalleled performance. Features: - Bio-Stretch Zone: Strategically placed 2mm panels (under arms and lower back) that allow for maximum range of motion - Core Power System: Internal support system that improves posture, enhancing hip rotation and lengthening stroke - 5mm Aqua Drive core body panel maximizes buoyancy and reduces drag - Thermo-Guard technology on chest, shoulders and legs to retain body heat - Quick-release ankle transition panels (horseshoe-cut design) for improved transition time - Extended length, reverse-pull zipper with leash for easy on/off and quick transitions - Aqua-Flex collar seal to keep water out and prevent chaffing and restriction - Super stretch, SCS-Coated Yamamoto 39 Neoprene for ultimate comfort - 100% UV protection