I needed a bass tuning tool for my studio. I've been a mechanic for over 34 years. One thing you will learn is to buy great tools for the job. Knowing that string height should be measured in 64 inches, I knew I needed a Starrett. for precision and craftsmanship. I still have 2 steel rulers that I used at the store. But I got these 2 for my studio to set up my guitar and bass. Love it ! .RW (Ruff Productions/Ruff Records)