F50i's upper adopts ADI's patented technology SprintSkin, which is made of light and thin materials, so that the upper fits the foot, just like the player's second skin. Moreover, the artificial material specially made by SprintSkin technology is softer and waterproof, and it is comfortable to wear for a long time. At the same time, the single-layer vamp effectively reduces the self-weight and resistance of the combat boots on the premise of maintaining the stability of the feet.
2. Heel
Like the F50, the heel of the F50i adopts a transparent design, which not only adds modern elements, but also thickens the heel to protect the safety of the heel and avoid injuries caused by sports.
3. Shoe studs
F50i adopts the design of 10 nail, with six nails in the forefoot, four nails in the heel, and plastic round nails in the shoe nails. It is worth mentioning that the F50i adopts the design of live nails, and athletes can choose to use them according to their different venues, including SG, FG or HG.