i H.S. 44.06 Railway or tramway sleepers of (cross-ties) wood;
ii H.S. 68.10 Railway or tramway sleepers of concrete and concrete guide-track sections for hovertrains;
iii H.S. 73.02 Railway or tramway track construction material of iron or steel, the following: rails, check-rails and rack rails, switch blades, crossing frogs, point rods and other crossing pieces, sleepers (cross-ties), fish-plates, chairs, chair wedges, sole plates (base plates), rail clips, bedplates, ties and other material specialized for jointing or fixing rails;
iv H.S. 85.30.10 Electrical signalling, safety or traffic control equipment for railways, tramways;
v H.S. Chapter 86 - Railway or tramway locomotives, rolling-stock and parts thereof; railway or tramway track fixtures and fittings and parts thereof; mechanical (including electro-mechanical) traffic signalling equipment of all kinds;
vi Construction work for civil engineering for railways falling under CPC prov. 51310 (Construction work for civil engineering for highways (except elevated highways), streets, roads, railways and airfield runways);
vii Construction work for civil engineering for railway tunnels and subways falling under CPC prov. 51320 (Construction work for civil engineering for bridges, elevated highways, tunnels and subways);
viii Repair and maintenance services of locomotives (including reconditioning), rolling stock (including reconditioning), railway tracks, traffic signals and installation services of railway engines falling under CPC prov. 88680 (Repair services of other transport equipment, on a fee or contract basis).