Brass Knuckle Ball Joints feature unsurpassed strength and durability. Utilizing the very best seal components in the world from NOK Japan, the quality, fitment, and tight tolerances of these Ball Joints far exceeds the industry standards. All ball joints use a Japanese metric thread (like the bikes for which they were designed!) and include a drilled stud with a castle nut and cotter key for added safety and ease of installation (If you have ever installed ball joints with the inferior nyloc design, you will appreciate this!). Always available, always correct, Sold in sets of 2.