Abstract: This adjusting device is applicable to terminals (2) which include a main body (11) provided with a linkage (19), and has on the main body (11), a housing (12) in which are set a regulating rod (22) provided with a threaded retaining portion (42), a thrust spring (23), two retaining bodies (20) provided with respective threaded retaining portions (26) which coincide with that of the rod (22), two retaining springs (21) and two fixing extensions (48, 61) of a fixing body (24). The fixing body (24) can take up two positions, one exterior position in which the retaining bodies (20) and the rod (22) are out of mesh, and an interior or control cable (3) length-adjustment position in which the bodies (20) and rod (22) are in mesh.