Body Armor Levels Explained: What NIJ IIIA, III, and IV Actually Stop
Body armor is rated by the National Institute of Justice (NIJ), the U.S. Department of Justice's testing body, and every legitimate manufacturer certifies its products against that standard. The rating tells you exactly one thing: which ammunition, at what velocity, the armor stopped in a lab test. It doesn't promise more than that, and understanding what each level actually covers is the first real decision in choosing body armor.
The short version
- Soft armor (concealable, wearable under clothing) stops handgun rounds. The current standard calls these HG1 and HG2; the older naming, still widely used, is Level II and Level IIIA.
- Hard armor (rigid plates) stops rifle rounds. Current naming is RF1 through RF3; older naming is Level III and Level IV.
- Soft armor does not stop rifle rounds. Hard plates are heavier, less concealable, and built for that specific threat.
The NIJ levels, side by side
NIJ updated its testing standard from 0101.06 to 0101.07, and renamed the levels in the process. Both naming systems are still in circulation, so here's how they map, along with the actual ammunition each level is tested against:
| Legacy level (0101.06) | Current level (0101.07) | Threat type | Tested against |
|---|---|---|---|
| IIA | (no direct RF2/RF equivalent, largely phased out) | Handgun | 9mm FMJ RN 124gr, .40 S&W FMJ |
| II | HG1 | Handgun | 9mm Luger FMJ RN 124gr at 1,305 ft/s; .357 Magnum JSP 158gr at 1,430 ft/s |
| IIIA | HG2 | Handgun | 9mm Luger FMJ RN 124gr at 1,470 ft/s; .44 Magnum JHP 240gr at 1,430 ft/s |
| III | RF1 | Rifle | 7.62x51mm M80 Ball NATO FMJ; 7.62x39mm mild steel core |
| (no legacy equivalent) | RF2 | Rifle | Same as RF1, plus 5.56x45mm M855 |
| IV | RF3 | Rifle | .30-06 M2 armor-piercing |
A few things worth being precise about, because this is where a lot of body armor marketing gets sloppy:
Level III and IV are rifle ratings, not "higher" handgun ratings. A common mistake is assuming the levels stack in order for every threat, so "Level III" sounds like it should stop more than IIIA, including bigger handgun rounds like .44 Magnum or .45 ACP. It doesn't. III and IV are a different category of test entirely, rifle rounds against rigid plates, not soft panels. Soft armor rated IIIA has never been tested against, and won't reliably stop, a rifle round.
"Multi-impact" and "stand-alone" are separate claims from the level itself. A plate's level tells you what round it stops. Multi-impact rating tells you how many hits it's certified to take in the same spot before it's built to fail. These are printed separately on a compliant spec sheet for a reason, don't treat "Level IV" alone as the whole story on a hard plate.
Backface deformation is part of the pass/fail, not a footnote. NIJ testing doesn't just check whether the round penetrated. It measures how far the armor deforms into a ballistic clay backing on impact, the standard's maximum permitted deformation is 44mm. Blunt force trauma from a stopped round is real even when the round doesn't get through, which is part of why properly fitted armor and a reasonable expectation of what "stopped" means both matter.
What MC Armor's own products are certified to
Every soft-armor panel we build, across the tank top, hoodie, and jacket lines, is certified HG2 / Level IIIA: tested against 9mm and .44 Magnum, front and back panels covering vital organs. Our hard-plate options step up from there, Level III/RF1 for a lighter, multi-impact-rated 7.62mm-rated plate, up to Level IV/RF2 for the highest rifle-threat rating we carry.
That's the practical decision most people are actually making: soft, concealable IIIA armor for everyday handgun-threat protection, or a rifle-rated hard plate carrier for a higher, specific threat profile. Neither one is "better" in the abstract. They're built for different things.
Frequently asked
Does a higher level always mean better protection?
Higher levels mean protection against a more severe, specific threat, not a strictly better version of the level below it. IIIA is the highest rating soft, wearable armor achieves. Going higher means moving to rigid plates built for rifle threats, a different product category with different weight, concealability, and cost tradeoffs.
Can soft armor be upgraded to stop rifle rounds?
No. Soft armor and hard plates work on different mechanisms; a soft IIIA panel isn't a lesser version of a hard plate; it's a different physical solution to a different threat. Products designed to accept both, like a plate carrier with pockets for hard plates, combine the two rather than upgrading one into the other.
What does "NIJ compliant" mean versus "NIJ certified"?
Certification means the specific product was independently tested by an NIJ-approved lab and passed. Always confirm the specific item and level you're buying was tested, not just that the brand generally works with NIJ standards.
Is there a level for both handgun and rifle threats in one soft panel?
Not in soft armor. A single soft panel is rated for one threat category. Combined protection means layering, hard plates worn over or alongside soft armor, not a soft product certified for both independently.
Sources: NIJ Standard 0101.06 and 0101.07 (nij.ojp.gov); MC Armor internal product certification sheets (Krypton, Sentinel, men's and women's tank top lines); MC Armor S33/Police catalog NIJ compliance chart.