The vacuum cups are made of high quality food grade 304 stainless steel, it's anti-corrosion and rust prevention. Our cups are BPA free and non-toxic so totally safe for you and your kids to enjoy. Used the vacuun-seal technology vacuum insulation for maximum temperature retention, keeping drinks hot for as long as 24hrs and cold for 12hrs . It's not easy to rust, corrosion and easy to clean. Anti slip bottle bottom and the reinforcement bottom, make the anti-breaking performance more stronger. The durable water bottle handle features an innovative design and a flexible grip . Leak proof screw cap lid, with food grade silicone stopper and silicone sealing ring, resistance high temperature, resistance aging, strong seal, durable used and unbreakable.