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Home / Connectors and Fasteners / 304 Stainless Steel Imperial Hex Socket Screws Fine Thread Bolts 1/4-20 5/16 3/8 1/2-13

Attributes

Brand -
Category Industrial Small Parts / Connectors and Fasteners
Origin -
Material 304 Stainless Steel
Drive Style Hex Socket (Allen)
Thread Type Fine Pitch (UNF/UNC Mix)
Head Style Button Head
Surface Finish Passivated
Sizes Included 1/4"-20, 5/16", 3/8", 1/2"-13
Package Quantity 200 Pieces Total
Hardness 70 HRB Minimum
Compliance RoHS Compliant
Country of Origin Imported

5 reviews

A

Anonymous

Mar 28, 2026

Rating: 4/5

Good Value

Solid screws for the price. One of the 3/8 bolts had a slightly burred head, but the rest were perfect. Would buy again.

A

Anonymous

Mar 25, 2026

Rating: 5/5

Perfect for Marine Use

I used these on a boat fixture. No signs of corrosion after three months of exposure. Very satisfied with the stainless quality.

A

Anonymous

Mar 11, 2026

Rating: 5/5

Excellent Thread Quality

Used these for a custom jig build. The threads engaged smoothly without any cross-threading issues. The 304 steel holds up well in my workshop environment.

A

Anonymous

Feb 28, 2026

Rating: 5/5

Great Assortment

Having multiple sizes in one kit saved me a trip to the hardware store. The hex sockets are deep enough for standard keys.

A

Anonymous

Feb 23, 2026

Rating: 5/5

Precise Measurements

I caliper checked the diameters and pitches. They match the SAE specs exactly. Great for precision assembly work.

5 FAQ

Q: Is a tax invoice included with the shipment?

A: Yes, as per our policy, a free special invoice is included with every order for your records.

Q: Are these screws suitable for outdoor use?

A: Yes, 304 Stainless Steel offers good corrosion resistance for most outdoor environments, though 316 is recommended for saltwater.

Q: What size Allen wrench do I need for the 1/4"-20 screws?

A: You will typically need a 3/16" hex key for the 1/4" button head screws. Please check the specific head size upon arrival.

Q: What is the tensile strength of these bolts?

A: These are standard 304 stainless fasteners, suitable for general mechanical applications. Specific load ratings depend on the size.

Q: Do these come with matching nuts?

A: This kit contains only the hex socket screws. Matching nuts are sold separately in our store.

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