Abstract: A safety valve incorporated in a tubing string has a diameter considerably larger than that of the rest of the tubing string. A cable protector is fastened onto the tubing string at the lead in to the safety valve to ensure that cables extending along the outside of the tubing string are able to cope with the changes in diameter without strain or damage. The cable protector is formed from two cast bodies and hingedly connected together to define a substantially circular inner cross-section. The upper body member is provided with an elongate cable slot in which the cable is received. In addition, the upper body member is shaped to give the cable protector an increasing internal cross-sectional size, or transverse dimension, along its length from one end to the other and, whereby the distance of the cable from the longitudinal axis of the tubing string increases as it extends therealong. Thus the cable received within the cable slot is guided along a path which has a varying spacing from the longitudinal axis.