The BlenderBottle Strada Stainless Steel push-button insulated protein shaker provides sleek style and ultimate ease. The shaker bottle’s spill-proof locking lid opens and closes with the touch of a button. A flexible, ergonomic carry loop provides a comfortable hold. The patented mixing system utilizes the BlenderBall wire whisk to mix even the most stubborn protein powder, and a rounded base ensures a smooth blend. Double-wall insulated stainless steel keeps drinks cold for up to 24 hours. Measurement markings on the inside of the bottle add to the ease of creating perfect protein shakes. Leak proof; top-rack dishwasher safe; BPA and phthalate free.