3 Wearbands is a resistance band training system the allows you to perform any movement at any speed, anywhere, while under full-time variable resistance. You can wear your own shoes, or no shoes at all, and receive a low-impact, purely functional resistance workout as your body naturally moves. Product Description Choosing Your Tier: Tier 1: Women under 53, Men under 55 Tier 2: Women 54 58, Men 56 511 Tier 3: Women 59 66, Men 6 66 Choosing Your Sock Size: XXS: Womens 5 & under, Mens 3 & under XS: Womens 6-8, Mens 4-5 S: Womens 9-11, Mens 6-8 M: Womens 12-14, Mens 9-11 L: Womens 15 & up, Mens 12 & up