Roadie helps you tune your guitar quickly and accurately, switch alternate tuning or create your own custom tuning. It takes Roadie a few seconds to fine-tune your guitar. The accompanying mobile app comes preset with 8 alternate and open tunings. It also gives you the ability create your own custom tunings. In noisy environments, switch on noise cancellation and let Roadie deliver its perfect, crisp tuning. Detection range: A1 (55 Hz) - A5 (880 Hz). Detection accuracy: Less than ±1 cent. Tuning accuracy: Up to ±2 cents. The reference A 440 Hz setting is customizable in 0.1 Hz increments from 420 Hz to 460 Hz. If you like to tune a string slightly sharp or flat or simply adjust that tuning in the app and tune back to it perfectly anytime. You can restring quickly using the automatic winding feature of Roadie. The motor rotates faster than 70 RPM. Roadie fits in your pocket or guitar case / bag. Size: 5x8cm / 2x3in Weight: 100g / 3.5oz.