3. The following class of lands and heritages is hereby prescribed for the purposes of section 6(1) of the 1975 Act, namely any lands and heritages in Scotland occupied by any posts, wires, underground cables and ducts, telephone kiosks, switchgear and other equipment not within a building, or by servitudes or wayleaves, and being lands and heritages occupied by British Telecom and used for the purposes of telecommunications services.