THIS ADVERT IS FOR A GREASE NIPPLE TO FIT A 4" PCD TRAILER HUB. THE GREASE NIPPLE HUB (4" PCD) CAN BE SEEN ON THE FOLLOWING VIDEO. IT IS A STRAIGHT NIPPLE AND SCREWS INTO THE FRONT SIDE OF THE HUB ALLOWING YOU TO PUMP GREASE INTO THE TAPER ROLLER BEARINGS.
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