Input tax credit availability: ducts and manholes in OFC networks treated as plant and machinery permitting ITC for telecom services. Ducts and manholes used as conduits and network nodes for optical fiber cable networks are treated as plant and machinery under the Explanation to the GST provision and therefore availment of input tax credit on such ducts and manholes is not barred by the blocked credit clauses that restrict ITC for immovable property or related works contract receipts.