BUTTON,LOCK,UPPER BEARING,LANDIN. Key specifications include material: STEEL OVERALL, head_style: FLAT CHAMFER, head_height: 0.368 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN, thread_class: 3A A, head_diameter: 0.550 INCHES MINIMUM AND 0.562 INCHES MAXIMUM IN, thread_length: 1.250 INCHES MINIMUM IN. This product is currently in active production with full OEM support.
This part is cataloged in the Federal Logistics Information System (FLIS) under NSN 1620-00-348-6293, indicating validated use in U.S. government and defense logistics supply chains. Available through authorized enterprise resellers and TPM (Third Party Maintenance) channels.
Verify compatibility with your specific system configuration before ordering.
| material | STEEL OVERALL |
| head_style | FLAT CHAMFER |
| head_height | 0.368 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN |
| thread_class | 3A A |
| head_diameter | 0.550 INCHES MINIMUM AND 0.562 INCHES MAXIMUM IN |
| thread_length | 1.250 INCHES MINIMUM IN |
| fastener_length | 2.460 INCHES MINIMUM AND 2.500 INCHES MAXIMUM IN |
| hardness_rating | 38.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM OVERALL |
| thread_direction | RIGHT-HAND |
| surface_treatment | OXIDE OVERALL |
| width_across_flats | 0.3125 INCHES MINIMUM AND 0.3160 INCHES MAXIMUM IN |
| internal_drive_style | HEXAGON |
| NSN | 1620-00-348-6293 |
| GENERAL CHARACTERISTICS ITEM DESCRIPTION | ALUMINUM BRONZE,QQ-B-666;O/A DIM 0.310 IN. LG;0.422 IN. OD;0.312 IN. ID IN |