3/8-16 UNC Grade 5 Hex Cap Screw 4 Inch

Imperial Grade 5 medium carbon steel hex head cap screw, 3/8 inch (9.5mm) diameter, 16 TPI UNC thread, 4 inches long for automotive and general machinery. Fully threaded with chamfered point. HTS 7318.15.80.66 applies to this US-standard cap screw over 6mm diameter.

Import Duty Rates by Country of Origin

Origin CountryMFN RateCh.99 SurchargesTotal Effective Rate
🇨🇳China8.5%+35.0%43.5%
🇲🇽Mexico8.5%+10.0%18.5%
🇨🇦Canada8.5%+10.0%18.5%
🇩🇪Germany8.5%+10.0%18.5%
🇯🇵Japan8.5%+10.0%18.5%

Alternative Classifications

This product could be classified differently depending on its characteristics or intended use.

7318.15Same rate: 43.5%

If for wood screws with coarse threads

Application-specific wood screws have dedicated coarse thread subheading.

7317.00.30.00Lower: 35% vs 43.5%

If not heat-treated (machine nails)

Non-headed or differently formed iron/steel threaded articles shift headings.

8708.80.65Higher: 52.5% vs 43.5%

If OEM auto body parts

Vehicle-specific fasteners may classify under auto parts Chapter 87.

Not sure which classification is right?

Our AI classifier can analyze your specific product and recommend the correct HTS code with confidence.

Import Tips & Compliance

Specify UNC/UNF clearly; metric equivalents can confuse examiners without diagrams

Grade 5 proof load testing docs required for structural claims

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