The HG Carbon Rear Bumper Plate and HG Carbon Rear Roller Stay (1.5mm) are now compatible with J-CUP2025. The elongated holes for the slide are 2.8mm, the pivot axle holes are 3mm, and the radius of the four corners of the spring hole is 0.5mm. To use three springs, you need to add spring retainers with scrap material as shown in the image. In the image, after the scrap material is glued, a pin made by stretching a hard spring is inserted.