From BruMate’s Website: The MultiShaker is made for elevating your fitness journey. Our built-in patent-pending agitator blends your shakes, greens, and powders without any clumps, while also serving as a water infuser for herbs and fruits. It includes our BevGuard™ insulation to keep ice for 24+ hours, a spill-proof MagFlip™ lid, volume markings on the inside, a durable silicone handle, a non-slip base, and the ability to interchange tops with our BevLock™ or Straw Lids, making it perfect for any workout or adventure. The new BevLock™ MultiShaker lid features a fully leakproof locking lid, so you can convert your MultiShaker into a leakproof tumbler and bring your favorite hot or cold beverage wherever, whenever. Fits all MultiShakers. Note: For use with the built-in agitator only. Do not install directly on the cup body.