Portable Guitar Finger ExpanderFinger Expansion: Effectively solve the problems of soft and weak fingers, hand collapse, and insufficient finger span. You can practice four fingers or two fingers. And Ring is 45 rotatable. Increase Span: This tool can help you quickly open your finger and increase the span; stretch the ligament and increase the strength to make the finger softer; continuous training can improve basic skills and exercise your fingers. Ergonomic Design: The