Rexroth DBD-type direct-acting relief valve 
 DBD-type valve is a direct-acting relief valve to limit system pressure, a total of seven pressure level: 2.5,5,10,20,31.5,5,40 and 63Mpa. The pressure regulator type: adjustable handle, lockable adjustment handle and adjusting screw with protective cover. Three connections: plate, pipe, plug-in. 
 http://www.jnlsl.cn/showproduct.asp?big=1&small=2&list=5&proid=21