ULTRACORE- Ballstretcher + Axis Ring - OXBALLSULTRACORE system is for the really big ballers that dig the most bag gripping stretch! You get the amazing CORE ballstretcherits got outer ribs for super long stretch: it stays taller on your sack with more padded grip in the middle for a fatty bag squeeze. You also get the rib gripping rubbery AXIS power ring its got channel ribs inside that morph with the outside ribs on the CORE stretcher. CORE ballstretcher is an amazing ballstretcher on its ownon