HEAVY-DUTY CHROME STEEL: Our steel rods feature hardened nickel plating for good corrosion and oxidation resistance. High quality heavy duty solid steel, has the characteristics of high load-bearing capacity and flexibility. Our strength training bars can hold 500lbs weight capacity. COMFORTABLE CURVED SHAFT: The ergonomic curved design puts the hand in a more comfortable position, effectively reducing the pressure in the wrist and forearm. The design of needle roller bearing can rotate, with excellent stability, and it is easier to turn the wrist. It can be used by beginners and professionals alike.