SHANGHAI, Aug. 26 (SMM)--SHFE lead prices opened higher then inched down, while domestic spot lead prices remained firm. Well-known brands such as Nanfang, Chihong Zn & Ge and Shuangyan were quoted between RMB 16,250-16,300/mt, with discounts extending to negative RMB 450-500/mt against SHFE 1110 lead contract prices. Goods supply for unknown brands was barely available in the market. Transactions were quiet ahead of the weekend.