N.A.T.O. The defensive military alliance formed in 1949 by ten european countries. WARSAW PACT A military alliance formed in 1955 by the Soviet Union Netherlands. Norway.
Tank Rings. Tank rings filled with gravel lift the tank above the surrounding grade. This keeps the tank out of standing water and increases the life of the tank bottom.
Typical O-ring and application. An O-ring, also known as a packing, or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface. The O-ring may be used in static applications or in dynamic applications where there is relative motion between the parts and the O-ring. Dynamic examples include rotating pump shafts and hydraulic cylinder pistons. O-