... Black / Machined, Annealed our company is a manufacturer of tool steel in Shaoguan City, Guangdong, China, engaged in the following ... steels:Cold work tool steel: like D2, D3, O1, S1, S7, etc.Hot ... work tool steel: like H13, H11, L6, etc.Plastic mold steel: like P20, 1.2312, 718, ... : xinlisaleeMSN: xinlisa(a)yahoo.com.cn special steel S7