Which type of lifejacket inflation:
Automatic Lifejacket Inflation. These life jackets work on the principle that an element in the inflation mechanism reacts with water (in most cases this is a pill/pellet that dissolves in water), automatically triggering the gas cartridge, which in turn inflates the air chambers of the lifejacket.
Manual Lifejacket Inflation. These lifejackets work by operation from the user, the lifejacket will have a pull chord or string that needs to be pulled firmly, this fires a pin triggering the canister to inflate the lifejacket.
Oral Life Jacket Inflation. The third method of inflating your lifejacket is by means of you manually blowing up the lifejacket. Located in the lifejacket where the lung is will be a mouth piece, this can be used as a fail safe to blow up the lifejacket, or to top up the air in an already inflated lifejacket.