The Matisse CX provides spectral linewidths below 20 kHz. This ultra-narrow linewidth is achieved by use of an intra-cavity electro-optic modulator (EOM) and the Pound-Drever-Hall stabilization scheme with a high finesse external reference cavity. Matisse C is a fully automated and compact single frequency ultra-stable, Out of Plane tunable ring laser that is ideal for Quantum and AMO (atomic, molecular and optical physics) applications. The Matisse C system has the industry’s highest output power, the narrowest external linewidth, and the broadest mode-hop-free tuning range. The compact, sealed, and fully automated design with broadband mirrors and specially developed optical mounts provide long term stability and truly hands free operation.