Walter pipette pumps are made of lightweight and durable materials and are designed to allow for an easy one-handed operation. Rotation of the thumbwheel draws or dispenses the liquid with precision and ease. The side lever allows the entire contents to be dispensed rapidly and efficiently. Each pipette pump is designed to work with both glass and plastic pipettes and are color coded to distinguish the different sizes (Blue=2mL, Green=10mL, Red=25mL).