1.OPTIMIZED TRAINING Improve your workout routine with this chest expander arm training device, which features an internal and external double spring design for even power distribution. Enjoy a stronger and more durable experience with gentle rebound and resistance to deformation, even after prolonged use. 2.GREAT STABILITY Our Triangle Gold Support Chest Expander Arm Training Equipment features durable construction with a multipoint support structure. Its positive and negative double triangle force structure allows for a r and more stable training experience. 3.Safe Material This chest expander arm training equipment is made of thick carbon steel frame and can withstand higher load thanks to the reinforced steel processing and lasts longer. 4.ANTISLIP DESIGN Feel and under control during intense workouts with the nonslip, highly wearresistant material of this chest expander arm training device, which improves grip and prevents slipping even when sweating.