Apollo Saturn V Instrument Unit Telemetry RF Directional Coupler, measuring 3.25″ x 11.25″ x 1.25″, with Marshall Space Flight Center label reading: "TM Directional Coupler, Pt. No. 50Z12586-001, Mod. No. 226, Ser. No. 022, Wt. 1.51, Mfd. by IBM, Cont. No. NAS8-14000." The metal plate is covered with foil tape and features four connectors marked "J1," "J2," "J3," and "J4."
