This is a small line tensioner made for my Two Up. I made a pulley mod for it and i was having a lot of issues of it loosening over time. I made this to enable me to simply tension the line much like a clothes line tensioner. Uses a M3 nut and bolt. Tested with 12lb fishing line (make sure that it doesn't stretch much).Tap center hole with M3 tap. ( DO NOT DRILL OUT TO 3MM! ) I found the best way to attach fishing line to bolt to allow spinning is to take side cutters right under the head and to cut about half way through the screw. This makes 2 channels that the line can be knotted on. Put a drop of super glue on it and it works fine. The nut on the backside acts as a jam nut and prevents the tensioner from backing off.