This basic hydraulic training aid is built on a sturdy welded structural-aluminum frame with heavy-duty casters for easy portability. The trainer is available as a single sided (-S) or a double sided (-D) unit and can accommodate up to four students per side. Each component is rigidly attached to the component panel to eliminate the potential for lost or misplaced items. Each component is labeled with a description and the correct JIC hydraulic symbol. All components are fitted with valved quick disconnect nipples, and hose assemblies with valved quick disconnect couplers are supplied. The hoses are used to connect the appropriate components to form a circuit presented in the lab manual. The lab manual for the hydraulic trainer contains 18 or more (depending on options) exercises to demonstrate basic hydraulic principles. Some of the principles demonstrated include directional control of a cylinder, sequence control of two cylinders using pressure controls, and proper flow control placement in a circuit. With the addition of the accumulator option, typical applications for an accumulator and discharge valve are demonstrated. Also there is available an electro-hydraulic option. This option replaces the solenoid valve on the basic unit with a proportional directional valve and electronic valve driver, and adds a position sensor to one of the hydraulic cylinders. This option provides the capability of demonstrating electronic proportional flow control and closed loop position control.