Abstract: A line tightening device, for use in removing slack from a flexible line has a plate-like body member. The body member has a pair of spaced holes and a pair of opposing ends. The holes are between the ends of the member. One end is bent generally at a right angle to the body member. At least one line receiving groove is provided along an edge of the bent up region. A flexible rope or line is strung through the pair of holes. The rotation of the body member in a first direction, around an axis substantially perpendicular to said first plane winds the flexible line around itself along an axis substantially midway between said two holes. This is repeated until the flexible line is taut. Then the flexible line is locked into one of the line receiving grooves. The line receiving groove is on the side of the body member that faces away from said direction of rotation, such that the device cannot unwind.