The CAP-CT Series has the largest visually clear infrared (IR) transmissive viewing area available. The exclusive pharmaceutical-grade reinforced Poly-View System polymer allows any thermography camera to monitor completely undisturbed assets inside energized electrical equipment in the visual, UV and shortwave, midwave and longwave IR spectrums. The larger rectangular viewing area provides an unparalleled field of view when compared to traditional round IR windows. The CAP-CT offers locking covers for your IR window. These are useful in areas of high traffic and protect the IR viewing panes from impacts, flying debris and dust. Constructed from aluminum, the CAP-CT series is recommended for all indoor applications.