Any Other Weapon (AOW) is one of the most misunderstood NFA categories. Here's what you need to know about fingerprints for AOW registration.
In This Guide
What is an AOW?
"Any Other Weapon" is an NFA catch-all category for:
- Weapons concealable on the person
- Disguised firearms
- Smooth bore pistols
- Certain modified handguns
If it doesn't fit the definition of a machine gun, suppressor, SBR, SBS, or destructive device—but is still NFA-regulated—it's probably an AOW.
Common AOW Examples
Disguised Weapons
- Pen guns - Firearms disguised as pens
- Cane guns - Walking canes with hidden firearms
- Wallet guns - Firearms in wallet holsters that fire without removal
- Cell phone guns - Firearms disguised as phones
Smooth Bore Pistols
- Handguns with smooth bore (no rifling)
- Some specialty shotgun-style pistols
Vertical Foregrip Pistols
- Pistols with vertical foregrips (in some configurations)
- Note: ATF rules on this have changed - verify current classification
Fingerprint Requirements for AOW
AOW fingerprint requirements are identical to other NFA items:
What You Need
- FD-258 fingerprint card
- Converted to EFT format
- Uploaded via ATF eForms
Individual vs Trust
- Individual: Your fingerprints only
- Trust: All responsible persons' fingerprints
Same as suppressors, SBRs, and everything else NFA.
AOW Tax Advantage
Here's where AOW gets interesting:
Transfer Tax (Form 4)
- AOW: $5 transfer tax (normally)
- Other NFA: $200 transfer tax (normally)
Making Tax (Form 1)
- AOW: $200 making tax (same as others)
- No $5 advantage for Form 1
2026 Note: With the $0 tax stamp, this advantage is temporarily eliminated. But when/if taxes return, AOW transfers remain cheaper.
Form 1 vs Form 4 for AOW
Form 4 (Transfer/Purchase)
Buying a manufactured AOW from a dealer:
- Standard Form 4 process
- Upload EFT fingerprints
- $5 tax (when applicable)
- Wait for approval
Form 1 (Make Your Own)
Creating an AOW requires careful consideration:
- $200 making tax (when applicable)
- Must understand what you're creating
- Some conversions are straightforward; others are legally complex
Common AOW Conversions
- Adding vertical foregrip to pistol (check current ATF guidance)
- Converting Mossberg Shockwave-type firearms (specific conditions)
Legal Warning: AOW classification is nuanced. What makes something an AOW vs SBS vs "firearm" depends on specific factors. Consult ATF guidance or an attorney before Form 1 AOW builds.
AOW Processing Times
AOW applications process the same as other NFA items:
- Form 4 eForms: 30-90 days typically
- Form 1 eForms: 30-60 days typically
No faster or slower than suppressors or SBRs.
