Can someone explain how this provides slope compensation data and is tournament legal? According to Appendix IV of Rule 14-3 no measuring device that calculates for slope may be used during tournament play.
First, the most important thing is to note that the local rules of a tournament MUST ALLOW rangefinder use.
The USGA changed rule 14.3 at the start of 2016 to allow the use of rangefinders that feature slope compensation with the stipulation that the player could not access that data while playing.
Some manufacturers built units that have interchangeable faceplates to control whether slope-compensation was available or not. On the Breaking 80 slope model rangefinder the slope feature can be toggled on/off with the press of a button. In other words, the unit can be set to give readings without slope data.
Below are links to the guidance information USGA sent out to manufacturers and to a video from USGA talking about the rule change.
But, again, it’s critical to make sure the local tournament rules allow rangefinder use.
Hope this helps.