90190-S04-000 Bolt Flange (12X38) - Overview. The 90190-S04-000 Bolt Flange (12X38) is a crucial component designed for Honda marine engine systems. This flange bolt, measuring 12mm in diameter and 38mm in length, plays a vital role in securely fastening engine mounts and other mechanical connections, ensuring parts remain perfectly aligned under various operational stresses. Manufactured to meet stringent OEM specifications, it guarantees seamless integration with existing parts, maintaining op