The SA200 family is comprised of Scanning Fabry-Perot interferometers, each with a free-spectral range (FSR) of 1.5 GHz. In each of these models the Fabry-Perot interferometer cavity has been carefully designed to be nearly athermal using the negative thermal coefficients of expansion of the internal piezo stacks to balance the small thermal coefficient of expansion of the Invar casing. With finesse in excess of 200 and a resolution of 7.5 MHz for the 1.50 GHz model these cavities provide an extremely precise and stable measurement platform. Additionally, the low scan voltage of 5 V per free-spectral range at 633 nm makes them easy to use and the confocal configuration of the cavity greatly simplifies alignment.