Finish specification

QQ-P-416 (AMS-QQ-P-416)

The federal specification for electrodeposited cadmium plating. It was cancelled in 2002 in favor of SAE AMS-QQ-P-416, but it is still the most-cited of the ten specs on this site in DLA's hardware catalog.

66,219 NSNs in DLA's catalog cite this spec. See the catalog data

What QQ-P-416 covers

QQ-P-416 covers electrodeposited cadmium plating. A callout names a type, for the supplementary treatment applied over the cadmium, and a class, for the minimum plating thickness.

Of the ten specs in this set it is cited on the most NSNs in DLA's catalog: 66,219, led by shear bolts, pin-rivets, sleeve bushings and close-tolerance screws, most of them steel.

Types and classes

Type I
As plated.
Type II
With supplementary chromate treatment.
Type III
With supplementary phosphate treatment.
Class 1
0.00050 inch minimum thickness.
Class 2
0.00030 inch minimum thickness. When a class is not specified, it is Class 2.
Class 3
0.00020 inch minimum thickness.

Status and revisions

QQ-P-416F, dated 1 October 1991, with Amendment 3 dated 17 March 2000, was cancelled by Notice 1 on 28 March 2002. The notice directs future acquisition to SAE AMS-QQ-P-416, which DoD adopted on the same date.

Drawings and catalog records written before 2002 still cite QQ-P-416. Check whether your order invokes the federal spec or the SAE document, and at which revision.

Typical applications

  • Corrosion protection for steel fasteners and hardware: shear bolts, pin-rivets, close-tolerance and socket head cap screws, machine bolts and setscrews lead DLA's catalog.
  • Parts made from alloy steels such as 4130, 4140 and E4340, which are the materials most often paired with it in the catalog.

What a shop needs to supply to QQ-P-416

  • Plate to the class thickness the drawing names, or Class 2 (0.00030 inch minimum) when no class is given.
  • Type II parts must show no white corrosion products of cadmium after 96 hours of salt spray.
  • Hydrogen embrittlement testing is required for parts heat treated to 160 ksi (HRC 36) or above.
  • Unless the order, end product spec or drawing says otherwise, bake parts for hydrogen embrittlement relief within 4 hours after plating, per the spec's bake tables. Do not flex plated springs and other flexing parts before that bake.

The purchase order, drawing and the revision of the spec it invokes govern. Always work from the revision your contract names.

QQ-P-416 in the DLA catalog

From DLA's public PUB LOG catalog, release 2026-10-27, covering 16 hardware and mechanical supply groups (fasteners, bearings, fittings, valves, power transmission, engine components and more).

66,219
NSNs whose catalog record cites QQ-P-416
53%
coded open to new sources (34,795 NSNs): at least one managing service codes it AMC 1 or 2 with AMSC G
26%
coded for existing or approved sources (16,958 NSNs)

Most common items

Bolt, shear6,837
Pin-rivet6,417
Bushing, sleeve4,601
Screw, close tolerance3,341
Bolt, machine3,105
Rivet, blind3,104
Screw, cap, socket head3,002
Washer, flat1,678
Setscrew1,518
Screw, cap, hexagon head1,292

Federal supply classes

5306 Bolts14,518
5305 Screws11,616
5320 Rivets10,186
5310 Nuts and washers9,815
3120 Bearings, plain, unmounted5,032
5315 Nails, machine keys, and pins3,978
5340 Hardware, commercial2,600
5325 Fastening devices2,314

Can a new source win these parts?

DLA codes each part with an acquisition method (AMC) and a suffix (AMSC). We count an NSN as open when at least one managing service codes it AMC 1 or 2 (competitive) with suffix G (the government has the full technical data and the rights to use it). Otherwise we count it as restricted when a service codes it AMC 3, 4 or 5 (buy from the manufacturer or prime) or uses a suffix that limits or conditions who can supply it (AMSC B, C, D, H, K, L, P, Q, R, T, U or Y): missing data or rights, source-control drawings, source or QPL approval, controlled castings, uneconomical breakout, an unstable design, or low-value screening for known sources. These are catalog codes; the solicitation always governs.

Open: AMC 1 or 2 with AMSC G34,79553%
Restricted: AMC 3, 4 or 5, or a restrictive AMSC16,95826%
Other acquisition codes3,2825%
No acquisition method in the catalog11,18417%

As of PUB LOG release 2026-10-27. How to read the codes: AMC and AMSC codes explained.

How catalog records call it out

Characteristic records that cite QQ-P-416 or AMS-QQ-P-416, grouped by the type, class or condition they name. Counted across the most common callout spellings, so the totals are a floor.

Type 2, Class 218,934
Type 2, Class 317,363
Type 1, Class 33,546
Not specified2,940

Materials these parts are made from

  • Steel (overall) 12,764
  • Steel comp 4140 or steel comp E4340 or steel comp 6150 or steel comp 873 (overall) 4,174
  • Steel comp E4340 or steel comp 8740 (overall) 2,023
  • Steel comp 4130 (overall) 1,902
  • Iron alloy 660 (overall) 1,498
  • Steel comp 4140 or steel comp 8740 or steel comp 8630 or steel comp 8735 (overall) 1,335
  • Steel comp E4340 or steel comp 4140 or steel comp 8740 (overall) 1,292
  • Steel comp 4130 or steel comp 8630 (overall) 1,126

Sample NSNs that cite QQ-P-416

Frequently asked questions

Is QQ-P-416 cancelled?

Yes. QQ-P-416F was cancelled on 28 March 2002, and future acquisition was directed to SAE AMS-QQ-P-416. Many drawings and DLA catalog records still cite QQ-P-416.

What do QQ-P-416 Type II and Class 2 mean?

Type II is cadmium plating with a supplementary chromate treatment. Class 2 is a minimum thickness of 0.00030 inch, and it is the default when no class is specified.

What are the QQ-P-416 class thicknesses?

Class 1 is 0.00050 inch minimum, Class 2 is 0.00030 inch minimum and Class 3 is 0.00020 inch minimum.

When is a hydrogen embrittlement bake required?

Unless the order, end product spec or drawing says otherwise, QQ-P-416F requires parts to be baked within 4 hours after plating, per its bake tables. Hydrogen embrittlement testing is required for parts heat treated to 160 ksi (HRC 36) or above.

Related

Sources