The iAU mounted on the outside of the bell is responsible for data collection from a number of sensors. Signals from the depth sensors, and optionally suit temperature sensors, connect to the iAU via a junction box inside the bell, known as the iBIS JB.
There is a digital display meter on the front of the iBIS JB to provide a local reading of ppO2 to the divers (note the ppO2 fuel-cell is located to the left of the display meter). The diver’s excursion umbilicals connect to Jupiter connector tails that come from the iBIS JB. These carry the diver depth transducer signals (and if installed – the diver suit temperature sensor signals).