Transmit-band coverage with dual polarization, in the smallest package in the S-band range. At 81 x 81 x 12 mm (3.2 x 3.2 x 0.46 in) and 100 g it adds minimal mass and panel area to the spacecraft. The usual role is as the omnidirectional complement to a directional array such as CSA-S-008-RH. The array carries the high-rate pass; this antenna maintains the downlink at every other attitude, including tumble and safe mode. Being passive, it draws no current and contributes no radiation-sensitive parts to the design. VSWR is 2:1 through an SMA female interface. Built for the harsh conditions of space operation across LEO, MEO and GEO, the sealed and vented housing addresses corona, multipaction, atomic oxygen and MMOD. Qualification is to NASA GEVS (GSFC-STD-7000) with random vibration to 14.1 GRMS overall across a -70 to +100 °C operating and storage range. ATH-S-007-DC is the matching dual-CP test hat. Certain small-volume orders can ship within days rather than the months typically quoted for space-qualified hardware.