Vollniete 100 degree solid rivets – flush shear head Titanium-Columbium alloy rivets 1. NAS1097U6-9 5000 St. ( i.e. NAS1097--> standardU Designates --> 45Cb TITANIUM COLUMBIUM ALLOY6 Designates the dash number of Dia i.e 0.188 inch9 Designates the dash number of length i.e 0.562 inch ) 2. NAS1097U6-20Quantity: 1500 St. ( i.e. NAS1097--> standardU Designates --> 45Cb TITANIUM COLUMBIUM ALLOY6 Designates the dash number of Dia i.e 0.188 inch20 Designates the dash number of length i.e 1.250 inch )