These syringes are designed to dispense volumes below 5 µl. This requires an extremely small tungsten plunger wire that travels to the tip of the needle. The resulting design has zero dead volume and is accurate below 50 nl. The 7000 series syringes are modified micro liter syringes with a plunger-in-needle design. The 7000 series is the only zero dead volume syringe available. The fine gauge tungsten plunger wire extends to the tip of the needle, ensuring that all solvent is expelled dispensing volumes from 0.05 µl up to 5 µl.