Feature:1. Durable and made of rubber, it is not easy to be damaged and can be used for a long time.2. The workmanship is beautiful and generous, with uniform texture, strong flexibility, and high airtightness.3. It is made by pasting four pieces of film to each other, then pasting and vulcanizing the film, valve nozzle and valve core.4. Not easy to deform, rubber has excellent resilience, insulation, water resistance and plasticity.5. Rubber bladder has valuable properties such as oil resistance, acid resistance, alkali resistance, heat resistance, cold resistance, pressure resistance, and abrasion resistance.Specification:Item Type: Rubber Squeeze BulbMaterial: RubberPurpose: laboratory gas collectionTube Outer Diameter: Approx. 9mm / 0.4inTube Inner Diameter: Approx. 6mm / 0.2inThickness: Approx. 0.8-1mm/0.03-0.04in.Package List:2 xRubber Squeeze BulbNote:1. Please allow 1‑2cm error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.