The Aviation PointTechnical data sheet · theaviationpoint.com/parts/washers/an960/
AN960 washer — flat washer, steel/alum/brass, inch sizes
Washer, Flat, from AN960 Rev. 21. Every row below is transcribed from the standard and has its own link.
AN960 at a glance
AN960Engineering drawing · dimensions in inches
Cancelled: use NAS1149. AN960 is cancelled (NAS1149 (AN960 Rev. 21 Notice 1, 16 Sep 2011)). Replacement named by the standard: NAS1149. The old number AN960-2L still turns up on drawings and IPCs: check the replacement for each part before you order. Each row below gives its own replacement number.
Specification
Item
Value
Type
Flat washer
Material
Carbon steel (MIL-S-7952), corrosion-resistant steel (MIL-S-5059, AMS 5510 or AMS 5512), aluminum alloy 2024 (Alclad) QQ-A-250/5 condition T3 or T4, or brass QQ-B-613 composition I or II; see codes
Locking
None (plain flat washer)
Item
Value
Finish
By code: cadmium plate QQ-P-416 Type II Class 2 (carbon steel); passivate QQ-P-35 (uncoated CRES); black oxide MIL-C-13924 (CRES); anodize MIL-A-8625 or chemical surface treatment MIL-C-5541 Class 3 / 1A (aluminum); natural (brass)
Procurement
FF-W-92
Status
Cancelled. Rev. 21 (6 Aug 1992) is inactive for new design, with NAS1149 substitutable in all applications; existing stock may be used until depleted. Notice 1 (16 Sep 2011) cancels AN960 Rev. 21 and says future acquisitions use NAS1149.
Dimensions by size
Dimension, in
No. 2
No. 3
No. 4
No. 5
No. 6
No. 8
No. 9
No. 10
No. 11
1/4
5/16
3/8
7/16
1/2
9/16
5/8
3/4
7/8
1
1-1/16
1-1/8
1-1/4
1-5/16
1-5/8
1-7/8
2-1/4
2-1/2
A — Hole diameter (bolt or screw clearance), tolerance ±.010
.099
.105
.125
.140
.149
.174
.188
.203
.234
.265
.328
.390
.453
.515
.578
.640
.765
.890
1.015
1.078
1.140
1.265
1.328
1.640
1.890
2.265
2.515
D — Outside diameter, tolerance +.070/-.005
.250
.250
.312
.438
.375
.375
.500
.438
.625
.500
.562
.625
.750
.875
1.062
1.188
1.312
1.500
1.750
1.812
1.875
2.000
2.062
2.375
2.625
3.000
3.250
T — Thickness (see note on tolerances)
.016 – .032
.016 – .032
.016 – .032
.042
.016 – .032
.016 – .032
.049
.016 – .032 – .063
.065
.016 – .032 – .063
.016 – .032 – .063
.016 – .032 – .063
.016 – .032 – .063
.016 – .032 – .063
.016 – .032 – .063
.016 – .032 – .063
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
.016 – .032 – .090
Maximum – minimum as tabulated in AN960 Rev. 21; letters as on the standard's drawing.
Part numbers
Every part number of AN960 Rev. 21, each with its own link. Codes (material, finish) build the full number in the box below.
Variant: Aluminum alloy 2024, anodized (MIL-A-8625) or chemical surface treatment (MIL-C-5541 Class 1A); inactive for new design since 30 Jun 1982, use J or K
D
Variant: Aluminum alloy 2024, untreated
B
Variant: Brass, natural (QQ-B-613 composition I or II)
(none)
Thickness: Regular thickness (the thickest listed for the size and variant)
L
Thickness: Thinner series (.016 on aluminum and No. 2 to No. 8 steel; .032 on larger steel sizes)
LL
Thickness: .016 on steel sizes where L is .032 (No. 10, 3/8; XC also 7/16)
Example
AN960XC616LL — Corrosion-resistant steel washer for 3/8 bolt or screw size, .016 thick, black oxide coated per MIL-C-13924
Every AN960 number and its replacement
375 pairs, as listed in AN960 Rev. 21 Notice 1 (16 Sep 2011). The old number stays valid on drawings and IPCs; the replacement is what to order.
Washer faces parallel within .002 in. Flatness: .007 for sizes up to and including 1/2, .010 for 9/16 to 1-1/4, .015 for 1-5/16 and larger.
J code (chemical conversion coating) washers are for use where low electrical resistance is required.
K code (anodized) washers are for use where corrosion protection is the prime consideration.
P code washers were reinstated from cancelled to inactive for new design as of 30 Jun 1982: use J or K code; P code may be used until stock is depleted.
Brass washers and No. 2 sizes were reinstated from cancelled to inactive for new design as of 30 Jun 1982.
The sheet strikes through the old thickness-code note (regular, L, LL and M series). Medium series (M code) was cancelled after 20 Jul 1984.
The thickness codes are not the same for all variants: compare the Thickness column, not the letters alone.
AN960 Rev. 21, 6 Aug 1992 — Washer, Flat — dimensions, part numbers and notes. Public domain, distribution unlimited. Notices: Notice 1 (16 Sep 2011): AN960 Rev. 21 cancelled; future acquisitions refer to NAS1149, Washer, Flat. After 6 Aug 1992 AN960 washers are inactive for new design; existing stock may be used until depleted; substitution per the interchangeability table (375 part numbers).
Educational reference only. not approved data. Always consult the applicable SRM, AMM, or AC 43.13-1B and your certifying authority.