size:75mm Material: ABS+TPE+Carbon Steel colour: Black + Red Package Contents: 1 x Hand Grip Ball 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. Unique Novel Design: finger strength exerciser adopts a unique design, 5 buttons correspond to your , the distance between the buttons is suitable, ergonomic, and helps you to exercise each one individually Finger and palm strength, flexibility and , increase -finger strength. Finger Strengthening Exerciser Balls Design: This finger ball exerciser has just the right squeeze to strengthen hand. These hand strengthener grips are effective for keeping the ball in hand during exercise, didn't , and didn't interfere with the alignment of during use. Customized Individual Buttons: adjustable for each finger to increase the force required to press each plunger and the silicon rubber pads are comfortable on the palm and finger tips. 3 Training Methods, Multi-functional Use: This finger strength enhancer provides you with a of training methods to support you in 5-finger training, 4-finger training, and -fitting training, and the training is in place and effective. Beyond that, it can be used for injury , stress relief, or any other activity that uses your grasping muscles. You can use it at work or even during your daily commute to relieve stress. Ideal training grip for rock climbers, guitarists, drummers, wrestlers or softball pitchers.