silicone o ring 1.hight quality,pass FDA/RoHS/PAHS 2.durable and corrosion resistance silicone o ringFeatures:(1)100% food grade silicone,FDA/RoHS/PAHS is approval,material is environment-friendly,nontoxic.if large quantity,we can offer any certificate as you requested.(2)durable,corrosion resistance,high tempreture resistance(3)many kinds of colour and size for your choice,the picture here is ...