One feature I love about the Garmin 800 is the percentage of grade reading. Unfortunately, due to my lack of speed on ascents of 15 to 20 percent, the Garmin does not register, and I am left guessing what I just climbed. This is where the Inclinometer from Cantitoe Road steps in. This device is a simple bubble level that shows both ascending and descending grade percentage. It attaches to the handlebars with a secure mount, and is easily readable while riding. The device is so simple, yet incredibly accurate, more so than computers that are relying on data from GPS that is read at intervals. If you absolutely need to know what kind of hill you are climbing at any given moment, the Inclinometer from Cantitoe Road is easily the best choice.