Hog D3 Zenith Regulator Package comes with the Hog D3 First stage, the Hog Zenith Second Stage, and a Low Pressure hose to give you everything you need in one purchase. The new D3 1st stage offers great performance in a small compact size. Designed with a hose routing of a Piston regulator, but the durability and cold water benefits of a diaphragm reg, the D3 is an industry innovation! The Zenith 2nd stage is a Pneumatically Balanced 2nd stage. The front cover has been redesigned to improve the performance, function, durability, and styling of the HOG 2nd stage. The Zenith utilizes a soft touch silicone center portion to provide the ease of clearing found in our HOG Soft Front Cover Accessory but with far superior durability. The Zenith also has new styling that helps to control free flow in current while also providing a cutting edge look to the regulator, so you can represent with style while breathing easy.