You cannot breathe directly out of a scuba tank because of the high pressure. A regulator reduces pressure to safe a level that can be inhaled by the diver. A diving regulator has two parts: the First Stage reduces the tank pressure and connects it to the Second Stage which contains the mouthpiece for breathing
The Ion is designed for high performance. “For such a small reg, the ION LT delivers quite a punch. It turned in stellar breathing-machine performance across Scubalab’s standard test levels. In ocean tests, divers loved this reg. It breathed dry and easy in all positions, and the full-cover purge got the job done.