There are 6 sizes available. S: 22.0-22.5cm M: 23.0-23.5cm L: 24.0-24.5cm LL: 25.0-25.5cm 3L: 26.0-26.5cm 4L: 27.0-27.5cm Please specify your desired size in the comments. Dieting insoles with 9 functions [Back] ・Impact protection zone Honeycomb-shaped heel pad reduces impact on the body. Enables more exercise ・Core ball function up zone Prevents ankle instability and enhances the effect of the core ball. ・Core ball zone Two core balls cause the user to lose balance upon landing, increasing muscle activity. ・Ultra-thin material Approximately 3mm, can be used in any shoes. [Surface] ・Heel zone Designed to fit the heel arch, it adheres perfectly to the sole of the foot. ・Adductor muscle assist zone Corrects the gait of people whose feet tend to open outwards. ・Ball of the big toe zone The indentation in the ball of the big toe makes it easier to maintain body balance. ・Inner arch zone Forms a vertical arch in the arch of the foot, fitting the sole of the foot firmly! You can walk a lot without getting tired even during exercise [Product Name] Core Muscle Exercise Insoles Twin Ball [Sizes] S size (22.0-22.5cm) M size (23.0-23.5cm) L size (24.0-24.5cm) Core training insoles, shock absorption, core strengthening goods Dieting insoles, core training insoles, shock absorption, arch support, core strengthening goods, shoes, core insoles, O-legs, core muscle exercise insoles, twin balls, core, core exercise, insoles, shoes, ultra-thin material, non-slip, walking, balance, muscle strengthening, calorie consumption, O-legs, 2 sizes available. Type...Other diet equipment