1.best seller chest expander 2.Durable,strong,safety 3. Non-toxic,eco-friend ... are acceptable.Nature rubber for human exercise-good for chest and back,durable,strong,good touch,soft,comfortable,portable, ... safe and environmental.Lifecycle:it can pull at least 20000 times.OEM design are acceptable.Environment ... .Certificate:CE,ROHS,REACH,MSDS,PAHS and EN71. Chest Expander