bkr bottle: soda lime glass, silicone sleeve, food-grade, BPA-free, phthalate-free polypropylene cap. bkr cup: borosilicate glass, silicone sleeve, gasket and button, BPA-free, phthalate-free plastic cap. compact cap: food-grade, BPA-free, phthalate-free plastic. straws & sleeves: 100% silicone which is derived from silicon a naturally occurring element.