The X-axis controls the left-right movement of the tool head. Unlike the carbon rod system of the X1/P1 series, the P2S uses a structure consisting of smooth rods and belts. The hollow, smooth steel rod offers performance on a par with carbon rods, whilst its smooth surface allows for easier cleaning and more convenient maintenance. Movement in the X direction is driven by the A and B stepper motors.
Further information can be found on the Bambu Lab Wiki.