From Instructions: This semiautomatic self-refilling syringe with spring loaded plunger allows repetitive delivery of present aliquots from a single reservoir. The handle has been designed to render fatigue free operation over an extended period of time. A detachable three way valve with corrosion proof springs and stainless steel check valve balls ensures a repetitive accuracy of +/- 1%.

Ruggedly constructed for long life, the Wheaton Self-Refilling Syringe features an interchangeable ground glass barrel with Viton washers for resistance to corrosion.Kanigen coated brass plunger and autoclavable.

In order to accommodate a wide range of Filling operations the Wheaton Self-Refilling Syringe are supplied with blunt end cannulae with Luer Lock, long and short chrome-plated intake/air vent cannulae, sinker and silicone tubing.

This unit is complete and has never been used. It even includes the warranty card and instructions. This syringe apparently came out of my laboratory and may be 20+ years old.  I did take it out of the box to insure that it still operated correctly.