A real bargain for you: This one is strong and sturdy. Manganese raceway and Dust proof ring are not something you'll see everyday. This one will last very long at minimum maintenance effort. The wheel is soft and protected by 2 covers.
Bracket K Series is made of steel up to 5.5 mm thickness, very strong and galvanized (Zinc) to increase rust resistance for the bracket. PP-reinforced TPU tires, so moving will not make as much noise as hard PA and PP wheels.