The first wheels are these blue wheels. I use these wheels to skate in the skate park especially on wooden floors. With these wheel I slip less. I like these wheels because they are strong.
The second wheels are green. I also use them in the skate park. They are even more severe than the blue wheels. When I use these I can skate well without slipping.
The fourth wheels a light colour. I use them to practise. I really like them. They are my favourite wheels.