Abstract: A self-locking electrical connector comprises a first connector element having a housing including a radially directed flange formed with radial slots, an internally threaded locking bush rotatably and slidably received on the housing and a stop ring fixed to the bush and formed with ratchet indentations distributed about the connector axis, a second connector element has a threaded body. A spring washer is axially retained between the stop ring and the flange. It has a plurality of keying fingers engaged into the slots for preventing mutual rotation of the housing and spring washer, is axially curved away from the housing between the fingers and is formed with projecting deformations located midway between the fingers for engagement into the ratchet identations by the resiliency of the washer.