HPI Racing 103348 Blitz Racing Spring Set, Front (4) HPI Racing offers a Racing Spring Set that gives BLITZ trucks a variety of tuning choices to dial in the handling of their trucks to track conditions This set features 4 pairs of gray front springs that are color coded for easy identification: Pink (Two steps softer than stock); White (One step softer than stock); Yellow (Stock BLITZ front spring); Red (One step stiffer than stock)