One workhorse of the ETA mechanical line is the ETA 2824-2, The 2824 is an automatic winding, twenty-five jewel movement, available in four executions or grades: Standard, Elaborated (improved), Top and Chronometer.
The Breather Valve is a protection device mounted on a nozzle opening on the top of a fixed roof atmospheric storage tank. Its primary purpose is to protect the tank against rupturing or imploding.
A: A piston is a cylindrical plunger that moves within a metal cylinder through the four strokes of the engine cycle: intake, compression, power and exhaust. While their motion is predicated on other engine parts and the mixture of air and fuel, the motion of a piston is central to the functioning of an engine.