Monoprice 113729 Nimbus 18AWG CMP-Rated Plenum Speaker Wire

The Monoprice Nimbus Series 113729 is an 18AWG, 2-conductor speaker wire carrying a CMP plenum rating, which certifies it for installation in the air-handling spaces found above drop ceilings and below raised floors in commercial and residential buildings. This rating is not optional in many jurisdictions — building codes and insurance requirements often mandate plenum-rated cabling in these spaces due to the reduced smoke and toxicity characteristics of the jacket material in the event of a fire. Monoprice addresses a common complaint about plenum cables by using a jacket material that is noticeably softer and more flexible than the stiff PVC typically found on plenum-rated wire, making it easier to pull through conduit and route around corners.

The conductors themselves are made from high-purity oxygen-free bare copper, which provides consistent electrical conductivity and minimizes signal degradation over the length of the run. The red and black color coding on each conductor simplifies installation by making polarity identification immediate and unmistakable. At 50 feet, this roll is sized for individual speaker runs in typical room layouts — enough to reach from an amplifier or receiver to a ceiling-mounted or wall-mounted speaker in most configurations. The cable is backed by Monoprice's lifetime warranty, covering manufacturing defects for as long as you own it.