Review on Gates 91107 Krikit V-Belt Tension Gauge, Black - Accurate Belt Tension Measurement Tool for Automotive Maintenance by Ryan Hampton

It's better than nothing. There are a variety of measurements, but if you measure often enough you can get an approximate value of around 10 units. The slower you drive, the better. Often the "needle" will move when it is removed from the tape. I'd say it's worth it compared to the $200 version of much better gauges. I wouldn't say it's very accurate, but you can get a lot of results within about 10-15 units. I just went with you