Xray have released yet another way to fine-tune your T3 or T2 based car with these new 4.9mm quick roll center holders. This matched pair of CNC-machined high-grade aluminium holders, marked H1 and H2, are 1mm higher with the same length than L1 & L2 holders, allowing the car to roll more. May be used at either front or rear. Using these in the front makes the car turn easier. Recommended for high-carpet traction tracks because it decreases in corner steering and helps to prevent traction rolling. Using the H roll-center holders in the rear increases corner steering and speed.