Description Product Reviews 18/4 Plenum Security Speaker Cable Stranded CMP Alarm Audio Signal 1000′ Plenum CMP Rated 18 AWG 4 Conductor Security Alarm Cable is made with 7 stranded bare copper conductors. It is unshielded with a CMP rated white colored jacket. Our Security Alarm Cable is available in 1000 ft. increments and is made in the USA. PLENUM RATED 18/4 1000ft Pro-Installer Series CMP,CMR,CL2 Rated for PLENUM, In-Wall or Riser Applications Professional Use Quality Stranded Copper Wire Conductors 0 Reviews Hide Reviews Product Reviews