The High Precision Series VOA is an ideal variable optical attenuator providing near-perfect performances. With a built-in position sensor, once the VOA’s attenuation value is set, it will remain at the value regardless of environmental variations. This series VOAs overcome the instability and drift issue associated with conventional VOAs. We produce three types to cover most application scenarios. The thermal actuated MEMS VOAs feature low loss of 1W, and linear response. It is available with all types of fibers of 125 μm outer diameter. We further produce high-speed feedback control VOAs with a faster response time of about 1 μs.