Xray XB9 progressive springs
Made for the XB808 and the XB9 are the new progressive springs from Xray. They feature softer rate at the beginning and become harder during compression to generate more grip and higher corner speed. They come laser-etched for easy identification, are available as pair and are usable on both the front and the rear of the buggy. Available as soft, medium-soft and medium type.
Source: Xray [teamxray.com]