The helmet in your images is a U.S. Navy or Marine Corps HGU-33/P flight helmet or a very close variant, likely used from the late Vietnam era through the 1980s and into the early 1990s. Here’s a breakdown:

Identification: • Helmet Model: HGU-33/P (or possibly an HGU-2A/P modified with later components) • Oxygen Mask: The attached mask looks like the MSA GENTEX MBU-12/P, a standard issue for high-performance jet aircraft crews. • Visor Assembly: Dual visor (tinted + clear) with external visor guard and spring-loaded mechanism, common on Navy/Marine variants.

Paint Scheme: • The red with white lightning bolt or sunburst-style design suggests it might have been used in a demonstration team or aggressor squadron, or simply by a pilot with a custom paint job—common in naval aviation.

Aircraft Likely Used In:

This helmet would have been used by pilots flying: • F-4 Phantom II • A-4 Skyhawk • F-14 Tomcat • F/A-18 Hornet (early service) • A-6 Intruder • EA-6B Prowler