The HOG Second stage gives you ergonomic one-handed access to both the inhalation effort knob and the dive/predive venturi adjustment lever, making perfect regulator tuning easy. The most important feature of the HOG technical second stage is the amazing breathing performance! The metal gas tube and precision components of this second stage allow for precision tuning for extremely easy breathing while also retaining heat and moisture from exhaled breath. This provides increased resistance to freezing in cold water and less dry mouth. The dual diver-adjustable features allow for condition-specific tuning during each stage of the dive. When paired with the HOG D1 or D1 COLD first stage, you can assemble a technical diving regulator that simply cannot be beat! Second Stage Only Adjustable 2nd Stage, Balanced 2nd Stage, Venturi 2nd Stage