Aquaculture Gear Boxes Taxable at 18% GST Under HSN 84834000: Tamil Nadu AAR

In re BAS-J Industries (GST AAR Tamilnadu)

Summary: The Authority for Advance Ruling, Tamil Nadu examined the classification and applicable GST rate of aquaculture aerator gear boxes and their spare parts supplied by M/s BAS-J Industries. The applicant manufactures, imports and supplies aquaculture aerator gear boxes and spares used exclusively in aquaculture aerators for rearing and maintaining the growth of prawns. The applicant had been classifying the gear boxes under HSN 84834000 and paying GST at 18%, but sought to classify them under HSN 84368090 as other agricultural machinery to obtain the concessional 5% GST rate under Entry No. 434 of Schedule-I to Notification No. 9/2025-Central Tax (Rate) dated 17.09.2025.

The applicant also contended that the spare parts and components used in such aquaculture machinery should receive the same concessional treatment. The Authority admitted the application under Section 97(2)(b) of the CGST/TNGST Act, 2017 concerning classification of goods. On examination, it noted that HSN 84834000 specifically covers gear boxes and other speed changers, whereas HSN 8436 covers specified agricultural, horticultural, forestry, poultry-keeping and bee-keeping machinery and parts thereof. The Authority observed that the applicant supplied gear boxes and spares rather than agricultural or aquaculture machinery falling under HSN 8436.

The fact that the gear boxes were designed exclusively for use in aquaculture aerators did not justify classification under HSN 8436. Applying the classification principles, the Authority held that the gear boxes remained classifiable under HSN 84834000 and attracted GST at 18% under the relevant entry of Schedule-II to Notification No. 9/2025-Central Tax (Rate). In respect of separately supplied spare parts such as bevel pinions, bevel gears, helical gears, helical pinions, worm shafts and worm wheels, the Authority further held that these were toothed wheels or other transmission elements presented separately and therefore fell under HSN 84839000 rather than HSN 84834000 or HSN 84368090.