D, for Digital.  The Sandel SG102/D Attitude Heading Reference System (AHRS) is identical to the SG102 (MOD2) without the analog interfaces. It's lighter in weight and lighter in price.  The SG102/D is designed for non-KG102 equipped aircraft and ideal for new equipment installs.

With an improved initialization time of one minute, it's 3X faster than the original SG102. It also comes with a selectable low- and high-speed ARINC 429 output, which allows for additional interface options such as radar systems, satellite communication antennas and FLIR stabilization.