The Apeks XL4+ is similar to Apex XL4 regulator except that it comes standard with second high pressure port. The extra high pressure port gives the option of an additional accessory, e.g. a transmitter
The Apeks XL4+ is especially well-suited for the technical exploration diver who prefers cold water climates. Compact and lightweight, it helps reduce jaw fatigue during long, cold dives. Designed with an innovative, over-moulded endcap in conjunction with the environmental diaphragm that helps prevent ice build-up. The XL4 makes an ideal stage regulator and is also an excellent high-performance option for the technical exploration diver who is serious about maximizing functionality and
First Stage

First Stage When the first stage is not connected to a cylinder valve, the Auto Closure Device (ACD) keeps the inlet shut to protect the first stage internal parts from contamination and corrosive water.
Exceptional cold-water performance. The LEG3ND’s integrated dry chamber keeps inner components clean and dry by isolating them from the outside environment. Deep ribs create a large heat exchange surface area that helps to prevent ice forming on the mechanism.
The new overmolded cap delays ice forming over the external diaphragm