Spot rubber finished firm on Tuesday. RSS 4 improved to ₹148 (147) a kg according to traders. The grade firmed up to ₹147.50 (₹147) and ₹144.50 (₹144) respectively according to the Rubber Board and dealers. RSS 3 (spot) slid to ₹151.16 (₹152.07) a kg at Bangkok. April futures firmed up to ¥281.2 (₹165.78) on the Tokyo Commodity Exchange. Spot rubber rates (₹/kg) were: RSS-4: 148 (147); RSS-5: 143 (142); Ungraded: 129 (128); ISNR 20: 128 (128) and Latex (60% drc): 93 (93).