Men’s boxer briefs Men’s underwear made from nylon/elastane Machine wash Imported Calvin Klein underwear style number U8520F Switch up your style with striped microfiber Slim Fit men’s boxer briefs from the Calvin Klein CK One collection. Designed to bring modern color and unparalleled comfort into your daily routine, soft and smooth Calvin Klein boxer briefs take everyday essentials to stylish new heights. Made of a lightweight stretch nylon microfiber blend, Calvin Klein CK One men’s boxer briefs feature a snap-button fly, smooth back with no seams, crotch gusset inseam for a better fit and a comfortable Calvin Klein microfiber waistband.