I just used this last weekend  Accu-Shot PRM (Precision Rail Monopod) Mid-Range (BT13) with Quick Knob Option follow this link click here http://bridgerguide.com/accu-shot-prm-precision-rail-monopod-mid-range-bt13-with-quick-knob-option/ for much more detail about it. Thanks and please repin if you like it. :)