A quality pendulum can be a boon to those shooters that don't have the confidence in visually estimating distance or just cannot acquire the confidence using 1 static pin.

Although a pendulum will work on most bows regardless of speed of bow, the faster the bow the better the single pin accuracy from 0 to 40+.

The best pendulums are the type that you can adjust to the setup of your bow (speed, weight of arrow, etc.) and quickly adjust height settings when heights of treestands vary.
ABS has the quality and capabilities to adjust.