The AERIS A1 regulator is a fantastic regulator at a fantastic price. The first stage is a very user-friendly system; its two HP ports and four LP ports allow you to configure your hoses in a manner that fits your gear and personal preferences. The A1 system is very low-profile and lightweight, two features that reduce your drag and increase your comfort while underwater. The first and second stages are incredibly durable and are easy to service during routine maintenance.