ISMAIL, J.

The matter relates to the assessment year 1968-69. The petitioners were finally assessed on a total and taxable turnover of Rs. 7, 92, 92, 517.87 and Rs. 6, 92, 51, 009.38 respectively by the Joint Commercial Tax Officer, Mount Road II Division, in his proceedings dated 31st December, 1969. The taxable turnover included a sum of Rs. 1, 90, 112 relating to the fitting of rubber tyres on metal tank wheels and top rollers for the Heavy Vehicles Factory, Avadi, assessed at 12 per cent. This amount was included in the taxable turnover returned by the dealers themselves. The petitioners did not file an appeal objecting to the assessment of any portion of the turnover. On 23rd December, 1970, the petitioners addressed the assessing officer requesting to revise the assessment for 1968-69 deleting the turnover of Rs. 1, 90, 112 and also to revise the assessment for 1967-68 in respect of similar turnover. The Joint Commercial Tax Officer, Mount Road II, Madras, by his proceedings dated 26th February, 1971, informed the petitioners that the assessments made for 1967-68 and 1968-69 could not be revised at that stage as final orders had already been passed. The petitioners