The straw cup spill stopper is a practical tool that prevents cup tipping and spills while also maintaining straw cleanliness. Suitable for work, sports, outdoor camping, barbecues, and other occasions.SpecificationColor: ClearMaterial: SiliconeStraw Cap Size: 0.9x8.5cm / 0.4x3.3 inch (ID*L)Round Stopper Diameter:  2.5cm / 1 inchSquare Spill Stopper Size: 2.5x2cm / 1x0.8 inchPacking List: 1 Set x Cup Stopper (2 Straw Cover Cap, 2 Square Spill Stopper, 2 Round Leak Stopper)AdvantageThe spill stopper is made of silicone material, which is flexible, durable and convenient to clean. The straw cap can prevent water from spilling out of the straw and keep dust out. The round stopper is installed on the inner side of the cup lid, which ensures sealing while allowing air to enter for easy drinking. The square stopper is installed on the outer side of the cup lid, securing the straw in place and forming a seal to prevent leak.InstructionThis silicone spill-proof stopper is designed for straw cups 2.0 30oz & 40oz.NOTE: Please confirm the required size and style before purchase.