Knit from Rothy's signature thread (spun from plastic water bottles). Soft, flexible upper -which means no break-in period, ever. Comfortable insoles Fully machine washable Our shoes don't stretch much-so make sure they are not too snug. Knit from Rothy's signature thread (spun from plastic water bottles). Soft, flexible upper -which means no break-in period, ever. Comfortable insoles Fully machine washable, so it's like new again and again. Our shoes don't stretch much-so make sure they are not too snug. Most customers recommend going up half a size for narrow feet and a full size for wider feet in this style.