Mares Plana Avanti X3 fins are the perfect combination of comfort and power for recreational divers and snorkeler's. The mid-sized blade has three channels for optimal movement. The fin blade is made of Tecraclene: blade with three channels for optimising water flow, the center channel is inverted to make better use of the glide stroke. The upper and lower stabilisers help maximise muscle energy conversion.   Tecraclene ribs in the foot pocket afford an improved fit and permit more efficient transmission of the kicking action. The range of sizes is complete, from XS to XL size to better accommodate all requirements, including those of women and younger divers. The straps feature the ABS Plus (Adjustable Binding System) for single-handed adjustment. The Mares Plana Avanti X3 is a successful marriage of comfort and power.   The Mares Plana Avanti X3 uses Mares patented design ABS Plus Buckles. It only takes one quick movement to easily open or close these buckles, even when wearing thick neoprene gloves. The double button release prevents the buckles from accidentally opening making them the most user friendly system on the market.   US Men's Shoe Sizes: US4-6 = Extra Small, US6-9 = Small, US9-11 = Regular and US11-13 = Extra Large US Lady's Shoe Sizes: US5-7 = Extra Small, US7-10 = Small, US10-12 = Regular and US12-14 = Extra Large Also check out  the variety of dive fins we carry visit : https://gs-diving.com/fins/ Also check out Dive Singapore for the variety of gears we carry visit : https://www.divesingapore.sg/product-category/scuba-equipments/