Steel 4320H AMS Number Alloy Type UNS Cross Ref. Spec Misc./Shape AMS 6299 4320H Steel H43200 AMS 6299 Bar 4320H Steel H43200 - Bar AMS 6299 Forging 4320H Steel H43200 - Forging AMS 6299 Tubing 4320H Steel H43200 - Tubing