Apollo CM Guidance and Navigation Computer Buffer Unit, measuring 6 x 4 x 6, with three connection ports labeled “J200,” “J202,” and “J203,” an orange light, and a power switch on the front. A parts tag affixed to the side reads, “Computer Buffer Unit, Guidance and Navigation, NAA/S & ID Control No. ME901-0666-0001…Motorola Part No. 01-24340F02, Motorola Serial No. A/4.” In fine condition. The Computer Buffer Unit was part of a system of pre-flight ground check out equipment to confirm the Apollo Guidance Computer (AGC) was fully operational for the lunar mission.