The Aerius II 545 provides a maximum of versatility. It is a large volume kayak that can safely carry two kayakers with extensive luggage through most adverse open sea conditions. Its secondary stability, unrivalled among kayaks, makes it the premier platform for kayak sailing. Yet the Aerius II is easy to handle alone, and thanks to the V-shape hull and its length moves swiftly on the water even when solo-kayaking it. Compared to the legendary Aerius II 520, the Aerius II 545 has a longer cockpit size, it gained space especially between the two seats, allowing considerably more comfort for the back seat, increased loading capacity and a slight increase in stability and speed. The versatility of Klepper's Aerius II resulted in a large variety of accessories being developed for this boat (see "Accessories" page). Owing to Klepper's well-developed construction the Aerius II is easy and fun to set up. With the help of a collapsible kayak cart the Aerius II can be moved in and out the water single-handedly, packed in 3 bags it can be transported in public transport, including common air lines.

The Aerius II 545 Quattro hull is made of very robust TPU that enables significant weight reduction compared to other skin materials. A special feature of the Quattro is a second set of air sponsons located below those that are standard also to Classic and Expedition. These additional air spnsons can be inflated partially or fully in order to gradually change the V-shape of the hull to a U-shape, adding primary stability in such uses as kayak sailing etc. By deflating the additional air sponsons, the hull shape is remodified to a V-shape within seconds, for such purposes as to paddle faster or longer distances.

The Quattro features a standard loading hatch behind the cockpit, with the option of another one in the front, is equipped with paddle pockets on the deck, and offers 4 deck colours and a 2-tone option to choose from.