1/4 Inch Helical Spring Lock Washer
Standard 1/4 inch helical spring lock washer from alloy steel, used with SAE bolts in automotive applications to resist vibration-induced loosening. The helical split design provides axial flexibility and locking tension. Falls under HTS 7318.21.0030 for helical spring lock washers.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If not helical spring type
Other lock washers (e.g., toothed or internal) go to the residual lock washer category.
If imported as vehicle part
If presented as a motor vehicle component, it may classify under vehicle parts chapter.
If machinery-specific design
Parts of machinery like engines could pull it to Chapter 84 if not general use.
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
• Include ASTM F436 or equivalent specs in documentation to confirm lock washer functionality
Related Products under HTS 7318.21.00.30
M4 Helical Spring Lock Washer
A small helical spring lock washer made of carbon steel, designed for M4 metric bolts to prevent loosening from vibration. It features a split ring that compresses under the bolt head or nut, creating tension. Classified under HTS 7318.21.0030 as a non-threaded helical spring lock washer of iron or steel.
M8 Zinc-Plated Helical Spring Lock Washer
Zinc-plated M8 helical spring lock washer of carbon steel for corrosion resistance in construction and machinery. The helical coil deforms to lock fasteners under load. HTS 7318.21.0030 covers these non-threaded spring lock washers.
M10 Stainless Steel Helical Spring Lock Washer
Austenitic stainless steel (AISI 304) M10 helical spring lock washer for marine and food processing equipment, offering high corrosion resistance. Its split helical shape ensures reliable fastening. Classified in HTS 7318.21.0030 as iron/steel helical lock washers.
5/16 Inch Alloy Steel Helical Spring Lock Washer
Heavy-duty 5/16 inch alloy steel helical spring lock washer for high-vibration truck suspensions and engines. Provides superior locking via elastic deformation. HTS 7318.21.0030 for these non-threaded helical lock washers.
M6 Black Oxide Helical Spring Lock Washer
Black oxide coated M6 helical spring lock washer for indoor machinery, reducing friction and corrosion. Helical design locks nuts effectively. Under HTS 7318.21.0030 as steel spring lock washers.
M12 High-Carbon Steel Helical Spring Lock Washer
High-carbon steel M12 helical spring lock washer heat-treated for maximum elasticity in heavy equipment. Prevents fastener rotation under dynamic loads. HTS 7318.21.0030 designation for helical types.