Suits 2022+ Float X only. 

Change the spring rate of your Fox Float air shock in just a few minutes with the new Float Volume Spacer kit. Reducing the volume of the air chamber causes the air pressure to ramp up more quickly, so the spring pressure can be set low, allowing more suspension sag without risking harsh bottoming. It essentially makes the shock feel more 'progressive'.

Fox part: 803-01-937 -  FLOAT X , FLOAT X NEO Air Volume Tuning Kit