>>UPDATED VERSION: Maxyonly series, much more heavy duty material Imported spring from Germany, super heavy duty stainless steel, orange color, diameter of spring is more bigger up to 52mm, much more powerful!!!.>>The Max power twisters are always same resistance as the begining even you bend it more than one million times. It will keep your power going up day by day!.>>Double Spring, more safety, more heavy duty! Perfect Arm and Chest Workout Equipment.weight Included: 50kg(110lb)/60kg (132lb)/70KG(154lb)/80kg(176lb)/90kg(198lb)/100kg(220lb)/140kg(308lb). This is 90kg level..>>Perfect Fitness Exercise Device: High quality Premium Materials and suitable & comfortable handle for portable comfort workout at home, Office or Travel.Perfect for building upper body strength. Suitable for people: professional player, exerciser and trainers..>>Package: 1 pcs of power twister & 1 pcs storage bag in nice box! 100%Customer Satisfaction- We guarantee 100% satisfaction on our product and service, any customer servises or inquiries are welcome to contact with us, Reply in 24 hours!