Disclaimer for internal research use restrictions: Any restrictions on the purchaser's sole use of products for internal research shall not apply to the products on the web page to which this statement relates. The term "leak-proof" applies to Thermo Scientific Nalgene products that meet the following conditions: a) Bottle/flask/funnel lid systems with lid sizes less than 100 mm, when filled with water and inverted for 2 minutes at 2 psig atmospheric pressure, internally The water will not overflow; b) For bottle/funnel/flask cap systems with cap sizes greater than 100 mm, when filled with water and inverted for 15 minutes, the water inside will not overflow. Note: If other liquids are used for the above test, different results may be obtained. To ensure safe use, customers are advised to test Thermo Scientific Nalgene bottles and closures under planned application conditions. Thermo Scientific Nalgene products are leak-proof when used with Nalgene caps at room temperature and pressure.