Overall, this is a pretty good T-Bevel. The digital protractor is a nice addition but I find that it can get offset pretty easily. I would only use this for reference angles or to just get a quick measurement. The battery seems to die fairly quickly if it is being moved around, since it has a auto on feature.
I do a lot of fancy wood working. You can use this T-bevel best to measure the angle of a cut. Using it like protractor, it is not going to work very since the 2 arms are not in the same plane, although they are parallel. Realistically, your saw does not cut perfectly straight to begin with, so measurements can vary depending on how and where you hold the T-bevel. It is not a straight edge, either, because the arms are too short.
This is a neat little device for the price. If you want high accuracy you will find yourself chasing precise measurements because it is a little flimsy and the sliders are short on these types of gauges. You should expect +/- 0.5 deg or so repeatability. It's accurate enough for most measurements and it should function as a regular bevel gauge as well as any other in this price range.
Got this for our patio. Works great! Have only used it a couple of times so far, but now we have it when we need it
The zapper is on my front porch hidden behind a plant, but the bugs find it instead of me. It is lightweight and easy to set up.
24-48 hours my pests were GONE.