I Believe Solid M80 with the Apogee core...
Heres info from another post
Columbia 300 is proud to introduce the newest addition to our product line... 10â„¢ by Columbia 300
Hard hitting Capstoneâ„¢ core meets with M80â„¢ to knock down all “10â€. We’ve lowered the Rg (2.45) and raised both the differential (.054) and intermediate differential (.025) in manufacturing the strongest asymmetric core in Columbia 300’s history. Combine the core with our proven M80 cover and you have a ball that will devastate the competition. The “10†from Columbia 300, it’s not just a number – It’s an attitude.
The 10 is available in Deep Purple with Neon Green/White engraving and is available in weights of 12 to 16 lbs.
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~Britton~
Columbia Industries=The BEST ball manufacturer
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