Addicts Relentless fork for the SCS compression system requires that you use the included headset spacer for the compression to become tight. The compression bolt is a powerful M8 bolt that ensures you a strong and durable compression.
You can ride wheels up to 115 mm in diameter and 24 or 30 mm wide wheels. Be aware that the crown race is not built in and there is no loose one with the fork. It is a good idea to buy a new headset when changing your front fork.