Flown Crewman Optical Alignment Sight (COAS) mounting bracket used on Apollo 9, measuring approximately 2.25 x 1 x 1, marked on the reverse, "06359-0180FKA, 41100-70131." Removably mounted with string and Velcro on an 8.25 x 10.25 display. In fine condition. Accompanied by a letter of provenance signed by Apollo 9 Commander Jim McDivitt, in full: "I certify that this COAS mounting bracket was flown onboard Apollo 9's LM 'Spider' on her first flight from March 3-13, 1969. It is from my personal collection." According to NASA: 'The COAS provides the Commander with gross range cues and closing rate cues during the docking maneuver. The closing operation, from 150 feet to contact, is an ocular, kinesthetic (eye, hand) coordination that requires control with minimal use of fuel and time. The COAS provides the Commander with a fixed line-of-sight attitude reference image, which appears to be the same distance away as the target.' There were two COAS brackets on the Lunar Module: one at the left forward window, and one at the docking window. As Apollo 9 represented the first-ever docking and extraction of a Lunar Module, this COAS bracket was an especially integral part of the mission.