bkr Straw Cap 500ml in N/A - NA. Size all. Our custom bkr Straw Cap is made for use with ourbkr Soft Silicone Strawsonly (no rigid straws please, it?s a safety thing). It?s made with the same BPA-free, phthalate-free food-grade polypropylene as the caps you know and love and has a clear silicone valve to hold your straw.. Splash resistant.. BPA-free and phthalate-free polypropylene plastic.. Removable silicone valve for cleaning.. Dishwasher safe on top rack. BKRR-WA46. CLCAPCA-T16HT. In 2011, best girlfriends Tal Winter and Kate Cutler launched bkr with a focus on one main concept which in their minds was Beauty 101: drinking water is the foundation for soft, dewy, pretty skin. The clean, addictive, cult favorite, small-mouth, original glass water bottle was sustainable and eco at its core, but it also made drinking water blissful and easy for a change, and people started noticing. A growing obsession with the pretty little bottle resulted in reports that people were finally truly hydrated and, as a result, they were looking and feeling better. And, as it's said, the rest is history.