SEPIA cryostat interior. Left: the cartridge cooling thermal links at 110 K, 15 K and 4 K temperature stages (purchased from RAL, UK) and the Sumitomo cryo-cooler integrated into the cryostat. All thermal connections are made via oxygen-free copper flexible braids to avoid vibration transfer. Below the bulkhead, the elements of the anti-vibration cold-head suspension system are shown. Right: SEPIA cryostat interior with ALMA Band 5 pre-production cartridge installed and the idle cartridge places blanked. Fiberglass support plates that also limit thermal conductivity flux sufficiently well providing the mechanical stability of the thermal decks.