Single-acting hydraulic cylinders (piston or plunger) and double-acting hydraulic cylinders (piston) are used in the hydraulic systems of cranes, hoists, construction machinery, farm machinery, etc. The single-acting cylinders come with an air vent (piston cylinders) or without an air vent (plunger cylinders). The complete cylinder includes mounting elements. The most common mounting element is an eye fitted with a grease nipple:

eye with spherical plain bearing (standard)
eye with bushing (option).
Eyes are welded directly to the cylinder and to the piston rod. A threaded eye can be screwed on a threaded piston rod as well.
Construction (with the example of HPA1 double-acting piston cylinder)

Parameter Name	Parameter Value
Type	hydraulic
Technology	piston
Configuration	double-acting single-acting
Other characteristics	standard threaded high-pressure welded
Stroke (mm)	300 - 300
Pressure	Min.: 0 bar (0 psi)Max.: 200 bar (2,900.8 psi)
Rod diameter	60 mm (2 in)
Speed (mm/s)	500 - 500
Ambient temperature	Min.: -20 °C (-4 °F)Max.: 100 °C (212 °F)