Description Equipped with good quality metal strings help guitar players to build calluses. This guitar chord trainer tool is a great gift to guitar lovers and players. A handy tool for guitar learners who still want to practice during trips instead of bringing the huge guitar. Due to its small and portable design, you can carry this compact device to keep up your daily practice. The tension of the strings can be adjusted with the tool included in the package to suit yourself. Specification: Color: as pictures shown. Size:3.7x5x31cm. Material: plastic, metal. Note:There might be a bit color distortions due to different computer resolutions. There might be a slight errors due to different hand measurement. Package included:1* set digital guitar trainer.