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Mil. Spec. Distorted-Thread Flange Nuts
Not only do these have the strongest hold of all the flange nuts we offer, they are also manufactured and tested to strict U.S. military standards for material and construction. They have irregularly shaped threads that grip the screw to resist loosening in high-vibration applications. The threads prevent the nut from backing out, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
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Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
Low-Strength Steel
 |
About half the strength of medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
Cadmium Yellow-Chromate-Plated Steel—Better corrosion resistance than plain cadmium. These nuts withstand salt water and are suitable for most wet and outdoor environments.
Flange | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Thread Size | Wd. | Ht. | Dia. | Thk. | Mil. Spec. | Certificate Type | Pkg. Qty. | Pkg. | |||
Cadmium Yellow-Chromate-Plated Steel | |||||||||||
| 2-56 | 1/8" | 3/32" | 0.167" | 0.01" | MS21042-02 | Material Certificate | 5 | 95307A800 | 00000 | ||
| 4-40 | 5/32" | 1/8" | 0.206" | 0.03" | MS21042-04 | Material Certificate | 5 | 95307A100 | 0000 | ||
| 6-32 | 3/16" | 9/64" | 0.244" | 0.03" | MS21042-06 | Material Certificate | 5 | 95307A200 | 0000 | ||
| 8-32 | 7/32" | 3/16" | 0.29" | 0.03" | MS21042-08 | Material Certificate | 5 | 95307A300 | 0000 | ||
| 10-32 | 1/4" | 3/16" | 0.33" | 0.03" | MS21042-3 | Material Certificate | 5 | 95307A400 | 0000 | ||
| 1/4"-28 | 5/16" | 7/32" | 0.42" | 0.04" | MS21042-4 | Material Certificate | 5 | 95307A500 | 0000 | ||
| 5/16"-24 | 3/8" | 17/64" | 0.52" | 0.04" | MS21042-5 | Material Certificate | 1 | 95307A600 | 0000 | ||
| 3/8"-24 | 7/16" | 9/32" | 0.62" | 0.04" | MS21042-6 | Material Certificate | 1 | 95307A700 | 0000 | ||
Mil. Spec. Nylon-Insert Locknuts
These locknuts are manufactured and tested to strict U.S. military standards for material and construction. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
Low-Strength Steel
 |
Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
Thread Size | Wd. | Ht. | Mil. Spec. | Insert Max. Temp., ° F | Certificate Type | Pkg. Qty. | Pkg. | |||
|---|---|---|---|---|---|---|---|---|---|---|
Cadmium Yellow-Chromate-Plated Steel | ||||||||||
| 4-40 | 1/4" | 5/32" | MS21044-N04 | 250 | Material Certificate | 10 | 95154A110 | 000000 | ||
| 6-32 | 5/16" | 3/16" | MS21044-N06 | 250 | Material Certificate | 10 | 95154A120 | 00000 | ||
| 8-32 | 11/32" | 9/32" | MS21044-N08 | 250 | Material Certificate | 10 | 95154A130 | 0000 | ||
| 10-32 | 3/8" | 9/32" | MS21044-N3 | 250 | Material Certificate | 10 | 95154A140 | 0000 | ||
| 1/4"-28 | 7/16" | 23/64" | MS21044-N4 | 250 | Material Certificate | 10 | 95154A150 | 0000 | ||
| 5/16"-24 | 1/2" | 23/64" | MS21044-N5 | 250 | Material Certificate | 5 | 95154A160 | 0000 | ||
| 3/8"-24 | 9/16" | 15/32" | MS21044-N6 | 250 | Material Certificate | 5 | 95154A170 | 00000 | ||
| 1/2"-20 | 3/4" | 19/32" | MS21044-N8 | 250 | Material Certificate | 5 | 95154A180 | 0000 | ||
| 5/8"-18 | 15/16" | 3/4" | MS21044-N10 | 250 | Material Certificate | 1 | 95154A190 | 0000 | ||
Mil. Spec. Thin-Profile Nylon-Insert Locknuts
These locknuts are manufactured and tested to strict U.S. military standards for material and construction. They are about half the height of standard-profile locknuts to fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
Low-Strength Steel
 |
Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
Thread Size | Wd. | Ht. | Mil. Spec. | Insert Max. Temp., ° F | Certificate Type | Pkg. Qty. | Pkg. | |||
|---|---|---|---|---|---|---|---|---|---|---|
Cadmium Yellow-Chromate-Plated Steel | ||||||||||
| 4-40 | 1/4" | 1/8" | MS21083N04, NASM21083 | 250 | Material Certificate | 10 | 95496A310 | 000000 | ||
| 6-32 | 5/16" | 9/64" | MS21083N06, NASM21083 | 250 | Material Certificate | 10 | 95496A320 | 00000 | ||
| 8-32 | 11/32" | 3/16" | MS21083N08, NASM21083 | 250 | Material Certificate | 10 | 95496A330 | 0000 | ||
| 10-32 | 3/8" | 3/16" | MS21083N3, NASM21083 | 250 | Material Certificate | 10 | 95496A340 | 0000 | ||
| 1/4"-28 | 7/16" | 7/32" | MS21083N4, NASM21083 | 250 | Material Certificate | 10 | 95496A350 | 0000 | ||
| 1/2"-20 | 3/4" | 5/16" | MS21083N8, NASM21083 | 250 | Material Certificate | 1 | 95496A380 | 0000 | ||
Press-Fit Locknuts for Sheet Metal
