SAPIM POLYAX BRASS OEM 2.0x14mm HEX SQUARE BLACKBulk Sapim nipples in a variety of styles see type column for part specifications Standard Polyax The round shape of the head of the polyax nipples work like a ball joint between the rim and the nipple ensuring a better spoke nipple line Secure Lock Locking mechanism that prevents nipples from untightening during wheel truing, machine compatible Double Square Allows the use of internal or external spoke wrenches wrench flats above and below the rim