Abstract: A device for measuring the pressure tension or pull force on a rope or cable. The device includes an elongated cable having a first end, a second end, and a midportion located between the first and second ends thereof; a support member; a pulley rotatably mounted on the support member, the pulley having an outer edge about which the midportion of the cable is wrapped; the pulley having a transverse slot through at least one edge thereof; the transverse slot having at least one opened end with opposing lips so that when the midportion of the cable is wrapped about the outer edge of the pulley and a pulling force is applied to one end of the cable, the opposing lips of the opened end of the slot will be urged toward one another an amount proportion to the pulling force applied to the cable; and a measuring mechanism for measuring the movement of the opposing lips of the opened end of the slot toward one another.