Description: Metal MaterialHand Wrist Forearm Strengthener is made from knurled aluminum handles and strong steel spring, sturdy structureSet of 6 PiecesHand Grip Strengthener Set includes 100 lbs, 150 lbs, 200 lbs, 250 lbs 300lbs, 350lbs to meet your different training needs. FunctionMetal Hand Grip Strengthener can build strength in the fingers, hands, wrist and forearms varied activities, including crushing, pinching and extension workSize InformationEach Metal Grip Strength Trainer measures approx 5.1inchx4.7inch, portable and easy to fit in bag or pocketApplicationHeavy Duty Hand Gripper great for men, women, seniors and teens, great for athletes(tennis, basketball, boxing, golf, etc.) and musicians (guitar players, pianists and violinists) Package Includes: Set of 6 Pieces Grip Strength Trainer 4 Pieces Sponge Cover Note: Please allow slightly errors 1-2cm differences due to manual measurement.