Limited edition plaque containing a 1.75" vial of flown polystyrene spheres, the "first space product," a material manufactured in space aboard the Space Shuttle Challenger during the STS-6 mission. The vial is housed within an 8" x 7" wooden plaque, numbered CM 4784 on the reverse, and displayed under a Plexiglas cover with Space Shuttle emblem and informational caption certifying its flown status: "These microscopic plastic beads are so small that 18,000 could fit on the head of a pin. They are used for the calibration of particle size measuring instruments including optical and electron microscopes." In fine condition.