Shop Klean Kanteen 12oz Kid Kanteent Sport w/ Sport Cap 3.0. Small and lightweight, the 12oz Kid Kanteen® Sport is the natural progression for kids who are ready for a more grown-up delivery system than the Sippy Cap. The entire cap is BPA-free, super durable and the new soft silicone spout makes the Sport Cap 3.0 safe for new teeth. The cap`s relief valve has been redesigned to be classroom-friendly, no chirping or whistling! The 12oz size fits into just about any cup holder, stroller, or car seat and its large-mouth design fits ice cubes and makes cleaning simple.