A linear operators is provided including a fixed linear body, a body guided and movable alternately on the fixed body with interposition of bearings, and at least one pneumatic or electric actuator to control the alternating movements of the moving body on the fixed body. The fixed and movable bodies (11, 12), are made up of extruded profiled elements. The extruded elements are of the same width and along each of the longitudinal opposite sides of each of the extruded elements a profiled groove (22, 23) is provided so that the collateral grooves of the two joined bodies are the same, parallel, positioned on the same plane and made to receive the fixing brackets for at least one control actuator.