33 81 00 Communications Structures
33 81 63 Cell Site Shelter Equipment
33 81 13 Monopole Communications Towers 33 81 16 Lattice Communications Towers 33 81 19 Guyed Communications Towers 33 81 21 Concealed Communications Towers 33 81 23 Broadcast Communications Towers 33 81 27 Aerial Cable Installation Hardware 33 81 29 Communications Vaults, Pedestals, and Enclosures 33 81 63 Cell Site Shelter Equipment 33 81 63.16 DC Rectifiers 33 81 63.19 Backup Batteries 33 81 63.23 Baseband Microwave Processing 33 81 63.26 Base Station Transceivers 33 81 63.43 Remote Monitoring