A valve-proportional solenoid arrangement is provided in a unitary housing. The spring elements of the solenoid are mounted within this housing in the nature of a clamped cartridge. Fluid movement through the valve is adjustable by either movement of the valve seat or the solenoid polepiece within the housing. The solenoid elements are secured into the housing by a threaded cap at one end. The valve elements are secured into the housing by a threaded cap at another end. In alternative embodiments, to assist in threaded securing of the armature to the retainer, portions of the circumference are flattened, although without altering the working area of the magnetic field with respect to the polepiece.