GST on Railway Parts supplied for supply to Railway

In re Prragathi Steel Castings Pvt. Ltd. (GST AAR Karnataka) Railway parts such as Couplers, Knuckle, Locks, Toggle, Yoke etc., manufactured and supplied by applicant to buyer Sanrok Enterprises (who in turn supply to Indian Railways after assembly) be classified under HSN 8607 or to be classified under HSN 7325 as other cast articles of Iron or Steel? Railway parts such as Couplers, Knuckle, Locks, Toggle, Yoke etc., manufactured and supplied by the applicant to M/s Sanrok Enterprises (who in turn supply to Indian Railways after assembly) are classifiable under HSN 8607. The applicable rate o...