Detailed Product Description 1), Material: Brass, nickel free2), Cap size: 12mm, 12.5mm, 13mm, 14mm, 15mm, 17mm, 18mm, 20mm, ... etc is available.3), Make up of four parts: cap, socket, stud, post( open post and close post)4), Common ... available.5), Can make customer's own logo on the cap and socket.6), High quality, reasonable price, best services.7 ...