The GXR has a modular design, consisting of two major components: the host body, which holds the battery, pop-up flash, rear screen, and external interfaces for data and flash; and a Camera Unit, which holds the image sensor, lens, and image processor in a sealed module.

[2] The body has a hot shoe on top for an external flash unit; the Ricoh GF-1 is designed for the GXR.

Alternatively, Ricoh marketed both optical and electronic viewfinders which attach to the hot shoe.

The GV-1 and GV-2 are optical viewfinders featuring the field of view equivalent to a 28 mm lens, and are intended to be used with the A12 28mm unit.

[5] Each Camera Unit (lens + sensor) has its own unique specifications relating to its sensor and optics, meaning that different lens units will change the features, behavior and performance of the camera body to varying degrees when attached.