This is the little desktop that pulls out from underneath the right side of the keybed of a Wurlitzer 214. These were found at the Wurlitzer warehouse. One is labeled with the part number (so there is possibly a document depicting it).
These can be installed underneath most tables, and can provide a convenient surface in any studio for drinks, effects pedals, etc. Because these desks were intended for the 214, they are extra-long compared to the pullout desks for the 206 and 206A.
Regardless of the color of the Wurlitzer, the pullout desk was always avocado green—a great 1970s detail.
Sold as a set of one (green) desk top and two slides.