ULTRA THIN LIGHTWEIGHT: Ultra-thin, no extra thickness, suitable for people who don't like to wear socks but need socks to isolate friction, suitable for designing tight-fitting shoes or boots COOL SENSE SKIN FRIENDLY: Cool and breathable, wearing ULTRACEN socks is like bare feet, enjoy the pleasure of bare feet, the wind can blow into the socks, suitable for summer or hot areas, people who don't like stuffy feet,Suitable for people who need special care for their feet, such as diabetics STAYS IN PLACE: The ankle strap is comfortable and grips your ankle, and the 3D heel design hugs your heel so you never have to worry about your socks slipping off your foot NO SHOW SOCKS: ULTRACEN socks suitable for booties, fit most sneakers, dress shoes, athletic sport shoes, boat shoes, casual shoes, canvas shoes and loafers, but not for very low cut shoes. TWO SIZE: These women’s thin invisible socks are available in US shoe sizes[ 5-7.5] &[ 8-10.5] This is a women's ultra-thin sock, specially designed for people who love breathable and lightweight. It's panelled with a breathable mesh upper and a sweat-wicking cotton base. It is suitable for summer or hot areas. Or people who like the feeling of being barefoot. And it is a style of invisible socks, which can be well matched with all kinds of shoes.