When worn on your midsection, the Slopegraide sensor forms a level with your hips, your legs, and the ground you are standing on.
As you stand on sloped parts of the green, your hips will naturally tilt down the slope. The sensor uses your lateral hip tilt to calculate the slope from where you are standing.
The Slopegraide app in real-time takes this slope measurement and calculates a rolling model for a putt from the specified distance and green speed parameters set in the app.
When the model is complete, the app displays a reference point that tells you approximately where to aim your putt. All of this is done in a second or less!