Secure Lock prevents nipples from loosening via a mechanical means instead of a thread locking compound or paste. Allows for truing and tensioning of wheel after wheel builds without any special procedures. Polyax design features a round shape of the head that works like a ball joint between the rim and nipple ensuring a better spoke/nipple line. Aluminum: 7075-T6 aluminum, special coating on thread and nipple surface to further reduce corrosion and reduce friction between spoke/nipple and nipple/rimItem Specifications: Length, 12mm, Color, Black, Material, Brass, Package, 100/Count, Gauge, 14g,.