This is Aqua Lung's complete regulator package for extreme cold-water diving.  It calls it the "Arctic" package, although each of the components can be used equally well in the Caribbean.

First stage:
It is made for the coldest environments, but will work equally well in the Caribbean. Upon information and belief, it is an Aqua Lung/US Divers Cousteau/SEA (yoke) model. Alternatively, it could be an Aqua Lung/US Divers Conshelf SE2 or SE3. Its high-tech features include an external rubber diaphragm at the end of the ambient chamber which is filled with oil. The parts kit (900001) for it is found at any Aqualung dealer.  It is an environmentally-sealed first stage regulator that brings the reliability and durability of the conshelf (Continental Shelf) to the coldest known conditions. Environmentally sealed first stages prevent water and silt getting in which prevents freezing in cold water. 

Second stage primary regulator:
The Aqua Lung/U.S. Divers’ “Arctic” model is a second stage regulator designed to be deployed in the coldest and harshest conditions in freezing temperatures and dove under icebeds with drysuits and heated clothing, but will work just as well in the Caribbean. However, it is purpose-designed for extreme cold, and is built like a tank. If you have ever wanted to dive frigid waters without worrying about equipment failure, you’ve now found the right gear to use! Arctic second stage parts kit (900008) is found at any Aqualung dealer. The Arctic is sought-after as a solid performer in freezing temps. See, e.g., the Lighthousediving website where the Arctic second stage and the Cousteau/SEA first stage are selling for $250.00 – and this third party seller includes no octopus or anything else like in the kit I am selling.

Octopus:
Upon information and belief, this second stage regulator model is the Aqua Lung XLC Second Stage a/k/a Calypso/Titan/Cousteau/Partner/Octopus, part number 104117.  This Aqua Lung Octopus second stage regulator is a high-quality scuba regulator manufactured in the United States. It was designed for scuba enthusiasts who value both high-performance features and durable construction. This unit is known for being made with high-quality materials, being bulletproof, and designed to last. Octopus parts kit (900013) for this model is found at any Aqualung dealer.

Gentle use with only four dives has carefully preserved this regulator set! Note the gorgeous condition of the first stage and the two second stage regulators!  You can see my reflection from all sides of the polished chrome (first stage)!

Comes with Aqua Lung Pivot “Supertilt” compass and combination tank pressure/temperature gauge that can comfortably turn for any viewing angle in a 360-degree rotation. The only sign of wear is that the plastic face of the tank pressure gauge is scratched from storage. By purchasing this kit, as with all used scuba equipment, you acknowledge that this scuba equipment should be serviced and/or inspected by a certified scuba technician before use. European service kits are also available as, respectively, 122204 (Arctic) and 122061 (Octo). I could not find what corresponding Euro part number the first stage is.

Ships lightning-fast tomorrow as long as tomorrow is not a Sunday.