Tune Your Baja 5B Suspension! Now available for the HPI Racing Baja 5B 1/5th scale gas buggy are these new Shock Springs that will help Baja 5B owners tune their suspension to track conditions for better handling. Each spring is color-coded for easy identification and the ends are ground flat so that the surface matches the spring perches. The yellow springs are softer than stock, the blue springs are harder than stock. Each package contains the springs needed for a pair of shocks. Includes two upper rear springs and two lower rear springs - four springs in total. 155mm total length, 23mm diameter, 2.3mm thick. HPI part # 86760.