Function introduction: universal for finger force instruments, streamlined design, more comfortable feel, conforms to the shape of the hand, not easy to fatigue when practicing soft silicone, fit design, each button is flexible and free, not loose, durable, blister packaging, not easy to break, Strength 5 Product: Beginner Piano Guitar Finger Exerciser Finger Instrument Applicable scene: all people who need to practice finger force Material: ABS+Silicone colour: red Package Contents: 1 x finger force Only 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.