Whether the activity of bullet proof body building ( in addition to fixing bullet proof windshield glass, bullet proofing of engine and fuel tank) on the motor vehicles ( 2.5 Ton capacity ) of Chapter heading 87 of the Customs Tariff Act, 1975, supplied by the customer (i.e. free supply) having Tarpaulin cover in the cargo compartment, is classifiable as supply of service under service classification head 9988 (ic) or 9988 (id) of the GST tariff attracting CGST and SGST of 9% + 9% / IGST of 18% under the provisions of the CST Act/ IGST Act 2017.