... international standards available. 1.material:iron2.the length of the ring clip have lots of sizes,all international standards available,and the ringhave ... shapes(D-ring,O-ring,Q-ring) and all of them can be made into pull open or trigger type.3.No.of ring:Can be ... time.Welcome to you inquiry.stationery,file folder,file clip ring mechanism/metal ring binder/metal binder/metal ...