With Profile's Aqua Cell, your favorite drinks are just a straw sip away! This durable, injection-molded system features two chambers so you can optimize your hydration with multiple drinks. The main chamber holds 35 ounces and the secondary chamber holds 15 ounces. And, the top caps open easily for on-the-go refills. The Aqua Cell also slips easily into Profile's Airstryke and Century aero bars (sold separately).