Abstract: An improved fluid level verification apparatus which may be manufactured or otherwise fabricated as a kit and assembled at a remote location for use on liquid filled containers and configured to reduce inherent mechanical stresses on the inspection tube and resists leakage due to environmental, chemical, thermal or mechanical expansion cycles by using internal grooves and entrapped o-rings.

Abstract: A single-piece piston for use in a pneumatically-activated pump or other metering device to meter a predetermined amount of lubricant or other liquid. The piston is disposed within a chamber of the body of the metering device. The piston has a grooved end that includes a head portion and a circumferentially-disposed angled channel for containing a sealing member such as an O-ring. An adjacent stem section includes means for providing a fluid-flow connection with the angled channel. Lateral movement of the piston within the body causes the sealing member to shift and block and unblock the fluid-flow connection means, which allows liquid from a liquid chamber to flow out the head of the piston's grooved end and to an adjacent pump chamber.