Spot rubber gained further on Tuesday. The market seemed to be suffering from acute short supplies while RSS 4 firmed up to ₹113 from ₹112 and ₹111.50 a kg respectively, according to traders and the Rubber Board. The grade improved to ₹110 (108.50) as reported by the dealers. April futures weakened to ₹116.55 (117.18), May to ₹118.69 (119.02) on the National Multi Commodity Exchange. RSS 3 (spot) closed higher at ₹100.17 (99.57) a kg at Bangkok. March futures slid to ¥166.9 (₹99.75) on the Tokyo Commodity Exchange. Spot rubber rates (₹/kg): RSS-4: 113 (112); RSS-5: 111 (109); Ungraded: 107 (106); ISNR 20: 107 (106) and Latex (60% drc): 80.50 (79.25).