Evelots Self Stirring Coffee Mug-Tea-Juice-Travel-12 ounces-Stainless Steel Quickly blends beverages without the effort of shaking or stirring. Constructed of durable stainless steel metal and a plastic interior that is BPA free. Battery operated (requires 2 AAA batteries, not included). Holds Up to 12 ounces of Liquid. Dimensions: 4.75"H x 3.5"D. Trusted vendor. For years Evelots has provided unique products with a 30 day easy return policy, and 100% satisfaction guarantee.