Type 1 Class A Borosilicate Glass that are designed for maintaining anaerobic conditions. Useful for studies involving methane-producing bacteria, cell culture, drug discovery, and research and development. Specifications: Sizes: 50ml, 100ml, 250ml, 500ml, 1000ml Supply With: 20mm Septum Stopper & Aluminum Seal Accessories: 2048-11800 Septum Stopper 2048-11020 Aluminum Seal 2048-10020 Seal