Features: 1. 24/29 joint, straight, two sides ears, and ground joint to hose connection. 2. With excellent sealing performance, standard ground glass apparatus is more suitable for some volatile and toxic substances or something that is required not to contact with rubber stoppers. 3. Made of borosilicate glass, environmental friendly, lead-free and stable material. 4. You can hold it firmly with standard ground design. 5. Low expansion, high temperature resistance, high strength, high hardness, high light transmittance. 6. It is commonly used in laboratory or industrial experiment.