This document was last updated on March 15th, 2020
The Fathom CCR uses low profile and extremely secure onboard cylinder mounts manufactured by Kent Tooling. The 220mm long mounts are made of 316 stainless steel and will hold anywhere from 3 to 8 L cylinders. A low profile single tank adapter, also made of 316 stainless steel, allows divers to use a standard backplate and harness. The onboard cylinder mounts and single tank adapter are secured to the scrubber canister with 316 stainless steel hose clamps, which gives the diver incredible flexibility in configuring the unit. For example, the Fathom CCR can easily be configured with 50 cf/8 L manifolded diluent/bailout cylinders for ocean diving. In the cave environment, we prefer larger side mounted bailout cylinders, so our typical configuration is 30cf aluminum or 3 L steel onboard cylinders, oxygen on the right and inflation gas on the left. For dives over 10 hours we replace the 3 L cylinders with 45 cf/7 L cylinders. Unlike most rebreathers, the Fathom CCR is designed to mount the onboard cylinders upright, which solves many of the trim issues common to rebreather divers. It also puts the valves in a protected and easily accessible position much like open-circuit doubles and greatly simplifies using a range of onboard cylinder sizes without having to change hoses.