SHANGHAI, Aug. 19 (SMM) –SHFE 1509 tin opened at RMB 106,650/mt on Wednesday. The metal rose to RMB 107,300/mt on exit of shorts, but then fell back to near RMB 106,960/mt. Finally, the contract and ended up RMB 120/mt or 0.11% at RMB 107,280/mt. Trading volumes were up 198 lots to 760 lots, and positions were down 162 lots to 1,364 lots. The price spread between spot and futures prices is too small, offering little room for arbitrage. This dampened trading activity. SHFE 1509 tin should test support at RMB 106,300/mt tonight.