Opto-mechanical fiber-optic attenuators are bulky and slow. The MARS (mechanical anti-reflection switch) modulator offers a high-speed alternative, with less than 10 microsecond response and 30 dB analog dynamic range. This talk describes a compact low-loss package with separate input and output fibers held in a single ceramic ferrule, a tiny (0.5 X 1 mm) gradient index lens, and a reflective MARS modulator in the collimated beam plane. This component has applications in telecommunications for line build out and dynamic amplifier gain control.