This is a pack of two optional XRAY Graphite 1-Slot Steering Block Extensions. These steering extensions are used to tune ackermann, effectively increasing or decreasing steering response. Available blocks: XRA322290: 2-Slot (standard) - turns outside wheels less, easier to drive, less aggressive XRA322291: 1-Slot - between a 2 and 0-slot XRA322292: 0-Slot - most aggressive steering, suggested for very technical small tracks