An electrical installation accessory comprising: at least one electrical installation pipe connector; and at least one strain relief element having a front end and a rear end and comprising a tubular body part an outer surface of which is substantially uniform over its entire length, wherein an outer diameter of the body part substantially corresponds to an inner diameter of the electrical installation pipe connector and strain relief means arranged to engage to an electric line to be pushed through the strain relief element in a direction from the rear end to the front end, and to prevent movement of the electric line through the strain relief element in a direction from the front end to the rear end, the strain relief element being arranged to be inserted, with the front end ahead, into an electrical installation pipe connector and to be fastened thereto, wherein the strain relief element is inserted, with a front end ahead, into the electrical installation pipe connector such that the strain relief element is fastened to the electrical installation pipe connector characterized in that the outer diameter of the tubular body part is about 16mm, 20mm or 25mm, and that the strain relief element comprises at least one restraint part located at the rear end and extending outwards from the body part of the strain relief element, the restraint part being an annular flange whose outer diameter is larger than the outer diameter of the body part of the strain relief element, and that the strain relief element comprises at least one sealing part, which comprises at least one membrane, which is made of a resilient material and substantially seals an opening passing through the body part of the strain relief element, the membrane being located in connection with the strain relief means, that the electrical installation pipe connector comprises fastening means which engage to the outer surface of the body part of the strain relief element upon insertion of the strain relief element into the electrical installation pipe connector enabling the strain relief element to be fastened to the electrical installation pipe connector. at least one electrical installation pipe connector; and at least one strain relief element having a front end and a rear end and comprising a tubular body part an outer surface of which is substantially uniform over its entire length, wherein an outer diameter of the body part substantially corresponds to an inner diameter of the electrical installation pipe connector and strain relief means arranged to engage to an electric line to be pushed through the strain relief element in a direction from the rear end to the front end, and to prevent movement of the electric line through the strain relief element in a direction from the front end to the rear end, the strain relief element being arranged to be inserted, with the front end ahead, into an electrical installation pipe connector and to be fastened thereto, wherein the strain relief element is inserted, with a front end ahead, into the electrical installation pipe connector such that the strain relief element is fastened to the electrical installation pipe connector characterized in that the outer diameter of the tubular body part is about 16mm, 20mm or 25mm, and that the strain relief element comprises at least one restraint part located at the rear end and extending outwards from the body part of the strain relief element, the restraint part being an annular flange whose outer diameter is larger than the outer diameter of the body part of the strain relief element, and that the strain relief element comprises at least one sealing part, which comprises at least one membrane, which is made of a resilient material and substantially seals an opening passing through the body part of the strain relief element, the membrane being located in connection with the strain relief means, that the electrical installation pipe connector comprises fastening means which engage to the outer surface of the body part of the strain relief element upon insertion of the strain relief element into the electrical installation pipe connector enabling the strain relief element to be fastened to the electrical installation pipe connector.