Spot rubber closed unchanged . RSS 4 quoted steady at ₹154 a kg by traders and the Rubber Board. The grade finished flat at ₹151 according to dealers. March futures slid to ₹147.81 (₹148.02), April to ₹154.10 (₹154.26) and May to ₹160 (₹160.27) while the June futures ended marginally higher at ₹162.99 (₹162.45) on the National Multi Commodity Exchange. Spot rubber rates (₹/kg) were: RSS-4: 154 (154); RSS-5: 142 (142); Ungraded: 128 (128); ISNR 20: 137 (137) and Latex (60% drc): 99 (99).