Description Made of premium rubber with good elasticity, smooth and hardwearing. Used for filtration assemblies, together with a flask for filtration. Resistant to chemical action, acids, and alkalis, except for hydrofluoric acid. Suitable for chemical and scientific research experiments involving decompression and filtration, to be used with filter bottles and filter paper. Features - Color: Green - Material: Rubber - Size: 8.40 x 8.40 x 3.20 cm / 3.30 x 3.30 x 1.26 inch - Set includes 9 different diameters for flexible use with various sizes of experimental filtration apparatus - Made of high-quality, durable rubber with good elasticity, smooth surface, and wear resistance - Can be used as a single assembly or to connect multiple apparatus - Helps reduce the risk of damage to glass stems during insertion or removal - Tapered collar design ensures a reliable seal for better experimental results - Good resistance to acids and alkalis Package list: 9 x stoppers