contained 38% copper powder.Regarding Backing seals,there are two different type. non-copper powder and contained copper powder. Contained copper powdercan reinforce heat dissipation.

*Accurate size ;if the size is not correct or non -complete,you can return your goods to company and we pay it.

if any interested our products please welcome to http://www.yfh-excavatorseals.com or contact me at :yfh@yfh-hydseals.com