STS-1 Crew Systems Flight Pocket Checklist, Working Copy (ring-bound & annotated).  Vintage 1980 program-used copy of the original STS-1 Crew Systems Flight Pocket Checklist.  This is a pre-flight copy used in preparation for the mission and bears several editorial corrections and annotations used to guide the preparation of the final version.  It is marked “Crew Systems Basic” on the spine in red marker.  Approximately 1" thick, with many interesting checklists and images.