Made of natural rubber, corrosion resistant, safe and durable for laboratory use. Suction ball has three valves which are used by elastic rubber force to help suck the solution into the pipette. Large suction force, not easy to crack, and the liquid is not easy to precipitate. Use with pipette, a good laboratory assistant. Suitable for industrial and mineral laboratories, agricultural laboratories, food laboratories, chemical laboratories and so on. Material: Rubber; Color: as shown in the picture; Size: 13*6*6cm/5.1*2.4*2.4inch. Package List:1 x Rubber Suction Bulb. Note: This product is only one-time use. Products should avoid rain and snow leaching, should be kept clean, prohibit the contact with acid, alkali, oil, organic solvent and other substances, and distance from the heat source 1.5 meters away. This product should be stored in a dry and ventilated warehouse, the temperature is 0-35℃, relative humidity is not greater than 80%, and the ground 0.2 cm above. The term of validity of this product shall be five years according to the above conditions.