Nutri Ninja 24-Ounce Double-Wall Stainless Steel Cup with Sip & Seal Lid for Nutri Ninja Blenders (XSKDWSS24), Stainless Steel Durable double-walled insulation keeps beverages colder for up to 4 hours (As compared to Ninja single-walled plastic cups when blended with ice and frozen ingredients) Slim design fits in most car cup holders, making it an ideal commuter companion for your nutrient juices Sip & Seal Lid for enjoying your drinks on the go Simply attaches to Pro Extractor Blades included with your blender. The Pro Extractor Blades are able to crush through whole fruits, vegetables, nuts, seeds, and ice BPA free, lead free, and phthalate free