patented extendable finger exerciser,a great practicing aid for beginner guitarists and pianists extendable finger exerciser is a perfect tool for beginner guitarists and pianists, helping to build up strength and reach with your ring and players:strength and flexbilliy is very important especially when playing challenging solo pleces where a high skill level is required and the is used a lot.for beginners:playing barre chords can be a tough challenge and the exerciser helps you overome the problem easily.tension range: 2.5lbs-6lbs.help the neglected reveresd finger practice( the finger lifting speed practice),which is often neglected the during the early days of tecching,and to assit skill development.beginner guitarists and other instrumenta players.Color:Black Name:Model Number:-10PType:Finger ExerciserMaterial:PlasticPackage Contents: 1* Finger TrainerOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.