Creeper for working under layout, discontinued by Micro Mark. $75, offers considered, local pickup only in Rutherford NJ.
from catalog description:
The steel frame is contoured to lift your body to the optimum position for reaching on benchwork, wiring and switch machines.
The softly-padded backrest with integral lever-action headrest inclines to three positions above horizontal to position your arms exactly where you need them and smooth-rolling industrial-strength casters let you glide about easily.
Overall size: 26 inches x 44 inches x 12 inches for easy storage