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.

Aerius II 545 can be fitted and sailed with all 3 available Klepper Sails, the "Drift Sail" designed mainly for tail winds, the full-saili [S1], and the very large full sail [S2] (for use with S1 on lakes, outriggers are recommended, for other use with S1 and any use with S2, outriggers are required). With S1 or S2 and outriggers, Aerius II can be used for the main purpose of kayak sailing, where paddling becomes an auxiliary function.