Gate Globe Check Valves

check valves
(Check valve) A device inserted into a moving liquid stream that allows flow of the stream in only one direction; most often used on the inlet and outlet sides of an HPLC pump.
A valve that closes to prevent backward flow of liquid
(Check valve) A check valve, clack valve, non-return valve or one-way valve is a mechanical device, a valve, which normally allows fluid (liquid or gas) to flow through it in only one direction.
(Check valve) used to provide flow through a pipe in one direction only. When installed between an external filter and the pond, it keeps the dirty water in the filter from flowing back into the pond if power is lost. They are also used to keep an external pump primed if power is lost.

globe
The earth
A spherical or rounded object
Earth: the 3rd planet from the sun; the planet we live on; "the Earth moves around the sun"; "he sailed around the world"
ball: an object with a spherical shape; "a ball of fire"
a sphere on which a map (especially of the earth) is represented
A spherical representation of the earth or of the constellations with a map on the surface

gate
A hinged barrier used to close an opening in a wall, fence, or hedge
A means of entrance or exit
A gateway
a computer circuit with several inputs but only one output that can be activated by particular combinations of inputs
a movable barrier in a fence or wall
supply with a gate; "The house was gated"