The biggest change Kevin made on the K4 hangars was an updated bushing seat: it creates extra lean turn. Aera trucks have been designed as a light weight truck for all speeds and all locations.
Not only have they been on the most racing podiums, and won more World Championships, they also have kicked butt on most freeride and slopestyle events around the world.
They are the choice of champions.
K4 trucks was designed with the input of multiple riders and the Aera Team. They were searching for the Answer = more lean more stability.
These trucks are on the 50 degree baseplate, most suited for freeriding and racers who like a lot of options. These trucks have a lot of lean, and can get you super precise and are a lot of fun diving through backmarkers in a race. If you style is sandbagging, and dodging through racers for the win...these are your trucks.
These are super limited, the last of the K4's in Australia...and maybe the world.