With the launch of the Reaction ARC, Columbia 300 is introducing a whole new element to core design - the patented ARC Block. In the past, most common high-performance cores utilized Flip Blocks on the top and/or bottom of the core. These Flip Blocks increased flare potential and caused the ball to "flip" on the backend. The Reaction ARC features ARC Blocks, which, when added to the top and the bottom of a high-density core, stabilizes the core and creates ARC in the mid-lane and a continuous backend motion. To create the new Reaction ARC, our team of engineers started with an inner core that has a differential of .154 (with traditional flip blocks), which is almost twice the legal limit according to ABC specifications. We took this high-density core and added low-density ARC Blocks to the top and the bottom. The ARC Blocks reduced the differential to .045, well within ABC specifications. The end result is a never-seen-before ball motion - ARC in the mid-lane and a strong, curving backend. The coverstock features our MegaTEC particle, which was developed to create more friction in the oil. Due to the strong hook potential of the Reaction ARC, it's available with a factory 1200 grit "Fine" finish. This is a smoother finish than 600 grit Sheen Finish used on previous balls. The Reaction ARC can be easily adjusted to either a higher polish (using TEC Shine) for added length or sanded for earlier ball reaction.