With the exclusive ON shaker cups, mixing-up even the largest and thickest protein or meal replacement shake is a snap. Each shaker cup has an Extra-Large 32 fl oz capacity and a 3 ¼” opening at the top that makes adding full-size ice cubes a simple proposition. Each cup also spec’d a beefy, deep-skirt cap that screws down tight to prevent leaking and a tapered bottom that fits into most automobile cup holders. And, unlike cheap knock-offs, this shaker is solid enough to survive dozens of cleanings…even in the dishwasher (top rack only). Last, but certainly not least, we’re proud to say that our shaker is made in the USA. Optimum Nutrition is proud to know that they are one of the few sports nutrition companies who own and operate their own production facilities. While it’s true that ON is one of the world’s largest producers of sports nutrition products, they remain focused on being recognized as the best. In fact, their requirements for raw materials are so strenuous that it’s not unusual for ON Quality Assurance Technicians to reject entire truckloads of raw materials that do not meet their high standards. They like to think that we take as much pride & care in crafting their award-winning supplements as our consumers do with crafting their physiques and fitness accomplishments.