For your consideration I have a NIB Roto Grip RST X-2 Squad Overseas Bowling Ball in 15lb. New 1st quality undrilled condition. Box has some minor wear.  Please find specs below. Thank you!

Gross weight - 15lb 4oz
Top weight - 3.71oz
Pin - 2.5-3"
Coverstock - MicroTrax Solid Reactive
Weight block - RST Core
Ball Finish - 3000 grit Abraion
Color - Purple/Navy/Black

RG - 2.53
Differential - .053
Mass Bias - .016