Features: Genuine knurled nut from aluminum ensure secure fastening for S, 4.2, D, and IS speaker systems, delivering professional durability. precisions machined aluminum construction features deep knurling for enhanceds grip during installation, for compatibility with sound equipment. for audiophiles, sound engineers, and technicians authentic replacement parts to maintain high end portable speaker systems. Perfect for studio setups, live event rigs, or home sound upgrades where reliable hardware ensures vibration resistant speaker connection. These nut preserve original equipment integrity, meeting rigorous demands of professional sound installations and collector grade restorations. Specifications: Materials: Aluminum alloy Size:21x5mm/0.83x0.2inch Knurled nut Package Includes: 1PC Knurled nut note: Please allow 0-1cm error due to manual measurement. make sure you not mind before bid. Due to the differences between different monitors, the Pictures may not reflect the actual of the item.