This is the KISS Injector, which is one of numerous product from Gordon Smith. Gordon and Jetsam Technologies Ltd. are the manufactures of the excellent KISS Rebreather. The name KISS is an acronym for "Keep It Simple, Stupid!". The KISS Injector has a metering orifice (a Swagelok 15 micron filter is used ahead of the orifice to insure nothing plugs it up) that slowly feeds oxygen into the loop at a rate slightly below the average metabolic rate of a diver. This is usually set to about 0.7 liters of oxygen per minute. If a diver is consuming 0.7 liters of oxygen per minute, they nothing needs to be done. If the diver is consuming more than this, then more oxygen needs to be added. This is done by operating a simple thumb-operated valve (the slotted manual injection valve button is found within the lower LH portion of the above image). A black Swagelok on/off valve & lever have been added in order to shut off the O2 injection during bail-out, this keeps the injector pressurized and water free, without continuous O2 injection.
The injector continuously adds the same amount of oxygen regardless of the diver's workload. In this regard it's essential that the O2 displays are prudently monitored.
The above image shows the two oxygen display gages and the triple O2 sensor array (composed of Delrin and made for me by Dave Sutton) which fits into the Dräger P-connector on the counterlung. Two of the O2 sensors are for the two display gauges while the third is routed to the wrist-mounted VR3 instrument via the male fitting seen above.
The stringed dust cap seen here, when removed, is where the male fitting seen in the above image links one of the three O2 sensors to the VR3.
I'm using the "Super Pony Tamer" to attach the He bottle to an aluminum 80 cu ft bottle filled with compressed air as a bailout.
This is a close-up image of the above "Super Pony Tamer" rig. The hardware for this setup is available in several kits from SRA (Reef Scuba Accessories, Inc.).
This is the 19 cu ft compressed air bail-out bottle used for shallow dives. Modified as a stage-rig bailout system.