Made of high-quality rubber material, corrosion-resistant, safe and durable for use. Easy and convenient to use, helps pipettes draw liquid using a rubber suction ball. The suction ball features three openings that utilize elastic rubber force to help draw the solution into the pipette. Take care not to draw the solution into the ball. Each opening is equipped with a small internal stopper in the rubber tube; pressing the side of the ball creates a gap between the ball and tube, allowing air to escape. The flow of liquid can be controlled by creating or closing this gap. Condition: Item Type: Quantitative Suction Bulb Material: Rubber Color: Red A Opening Diameter: Approx. 11.2mm / 0.44in Hole Diameter: Approx. 5.7mm / 0.22in E Opening Diameter: Approx. 12.8mm / 0.50in Hole Diameter: Approx. 7.6mm / 0.30in S Opening Diameter: Approx. 14.4mm / 0.57in Hole Diameter: Approx. 7.1mm / 0.28in Weight: Approx. 46g / 1.6oz Package List: 1 x Quantitative Suction Bulb