Item DescriptionSeal your liquid bottles tightly with Labelmaster's Phenolic Caps With Teflon® Liners. These have the excellent chemical resistance of Teflon with the compressibility and sealing properties of polyethylene foam. The plastic caps fit a 300 or 500cc glass bottle, or a 625 or 950cc glass or poly bottle with a mouth size of 53/400. Typical uses include analytical lab samples, high purity chemicals, strong acids solvents, environmental samples, pharmaceuticals and diagnostic reagents.