I bought some project x 6.0 shafts of good old eBay, but a few of them contain something in the bottom of the shafts.
Could someone please tell me what they are for and there purpose.
I'm guessing a weight plug. Not all clubheads are spot on in weight so eight plugs, or lead powder followed by a cork at the bottom of the shaft will be added to get it close to matching the other irons in the set. With PX shafts it could even be more needed since the shaft weight varies from club to club, on purpose, longer irons are lighter and shorter irons are heavier.