Belt drive bikes may be few and far between, but we find them to be something special for the bikepacker, and even daily commuters who like the idea of grease-free drivetrains. Maybe it's the internal gear box that stays squeaky clean through snowy mountain passes, and sandy seashores, or the reliable, never stretching belt, but either way when we see them we know there's a level of commitment behind the rider who calls that bike their own. There is a time, however, when you need to check the tension of your belt drive, and sort out your dropouts to make sure you're ready for that big trip, and that's where the Park Tool Belt Drive Tension Alignment Tool - BDT-2 comes in handy. Simple to use, the BDT helps you set tension, and gauges rear cog parallelism and angularity for a smooth ride.