Here is a picture of mine, sorry about the bad pic. Mine is a about 4" with a hole drilled in the middle just big enough for the pencil to slip through, you can use a set screw but I found that if it is tight enough It works easier. I use this during the long string tillering stage to get things bending evenly down to about brace heigth. Basically just get your bow bending and place your stick where it is bending the most on the limb, adjust pencil til It almost touches and then run It up and down the limb, where there is pencil marks is where you take off wood. Once your bending evenly you can start goin for draw weight, occasionly checking with the stick to see any small hinges that may have occured. Really is super easy to use and makes some great tillerd bows. Catch is you better be working with some straight wood, as in no kinks or character or It is pretty useless. Works best on backed bows.
Also ,I better give props to Eric Krewson for making Dean Torges' walkie talkie even better. Pretty sure that is who Lennie was talking about.
[attachment deleted by admin]