The ruler is convenient sized and has multiple scales for multiple tasks, almost all you could think you would need to adjust your guitar or bass. However, I'm very disappointed to the quality where there are 2 major problems -
1. the measures are not accurate, which by definition makes the rules utterly pointless.
2. the measures are not laser carved on the surface, but are painted and it only takes very little to wipe the paint off the surface.
Still the ruler can be used if you are not looking more than a half decent not so accurate guess or want to use it just to duplicate measures from setup to setup, but do not trust the figures that are on the ruler.