The XTX50 Octopus has a breathing effort control knob. This allows the diver to desensitize the unit when it not being used. The XTX purge buttons are large and easy to operate. A 2-stage progressive purge is used - press the purge on the side for a lower flow rate, useful where more control is required such as filling lift bags etc, then press in the centre for the full effect of the purge, i.e. when regulator clearing etc. Can be converted from a right-handed hose configuration to a left handed one. The process of changing the regulator to a left-handed configuration is both quick and simple. However, this procedure must ONLY be performed by an APEKS Authorised Service Technician.