27 13 00 Communications Backbone Cabling
27 13 33 Communications Coaxial Backbone Cabling
27 13 13 Communications Copper Backbone Cabling 27 13 13.13 Communications Copper Cable Splicing and Terminations 27 13 23 Communications Optical Fiber Backbone Cabling 27 13 23.13 Communications Optical Fiber Splicing and Terminations 27 13 33 Communications Coaxial Backbone Cabling 27 13 33.13 Communications Coaxial Splicing and Terminations 27 13 43 Communications Services Cabling 27 13 43.13 Dialtone Services Cabling 27 13 43.23 T1 Services Cabling 27 13 43.33 DSL Services Cabling 27 13 43.43 Cable Services Cabling 27 13 43.53 Satellite Services Cabling