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Square-neck bolt lock washers are essential for preventing fasteners from loosening due to vibration or thermal expansion. Ensuring a secure connection is crucial in applications ranging from automotive repairs to structural assembly. Selecting the appropriate lock washer guarantees long-term stability and safety for your projects.
Material: Carriage Bolts are made of 304 stainless steel, the carriage bolts and nuts kit is strong and reliable, resistant to corrode, making them suitable for both indoor and outdoor applications
Well Made Carriage Bolts: All of the stainless steel bolts and hex nuts and flat washers are well manufactured with no burs, smooth-symmetrical head, precise and clean threads
Material: Carriage Bolts are made of 304 stainless steel, the carriage bolts and nuts kit is strong and reliable, resistant to corrode, making them suitable for both indoor and outdoor applications
Well Made Carriage Bolts: All of the stainless steel bolts and hex nuts and flat washers are well manufactured with no burs, smooth-symmetrical head, precise and clean threads
Strong Carriage Bolts: Carriage bolt is dome head bolt fastener with a locking neck style, which prevents turning when the nut it tightened or removed. Can be used in wood, metal applications
Stainless Carriage Bolts: Our 304 stainless steel carriage bolts 3/8 are of excellent corrosion resistance and durability. These carriage bolts 3/8 x 2-1/2 are ideal for both indoor and outdoor use
Well Made Carriage Bolts 2-1/2 Inch: All of the stainless steel bolts and hex nuts and flat washers are well manufactured with no burs, smooth-symmetrical head, precise and clean threads
Complete Bolts Nuts Washers Kit: You will get 6pcs 3/8-16 x 2-1/2" carriage bolts, 6pcs 3/8-16 hex nuts, 6pcs 3/8" ID flat washers in one package. Standard size, the bolt conforms to ASME B 18.5
Size: Diameter 1/4 inch, Length 1-1/2 inch-20 UNC Full Course thread Comply with ASME B1.1 standard;there are no issues of thread stuck damaging to compare with nonrust steel bolts in high and low temperature environments
Requirements of SAE J429/ASTM A307/ASME B18.2.6 for material,mechanics,dimensional inspection level to make sure the bolt and nut have much more strength,duraility, and reliability; ASTM F1941/ASME B18.18.2M/ASTM B117 surface treatment with SC2 to SC...
Nylon Insert Hex Lock Nut have more strong and long lifetime,full course for thread clamping force to avoid loose on vibriation,shocking,earthquake situation; large size flat washer apply for much more worse work conditions.
Square neck underneath the round head feature as suit for their self-locking when position in square hole for nut tighting; Bolt, Nut and flat washer pack up together as one unit for conviences to end user with easy installation experiences.
Thread Size: 1/4-20; Thread Pitch: 20 TPI; Thread Type: Coarse Thread; Screw Head Diameter: 0.58" (14.8mm); Round Head Height: 0.12" (3.2mm); Length (including the neck): 2-1/2 inch.
Package Include: 10 PCS 1/4-20 x 2-1/2" Carriage Bolts, 10 PCS 1/4"-20 Hex Nuts and 10 PCS 1/4" ID Flat Washers.
Material: The Carriage bolts kits are made of carbon steel with black coating, which have greater strength and corrosion resistance performance than regular zinc plated fasteners.
Feature: The carriage bolts have round heads and square necks. The square neck locks the square receiver hole to prevent rotation. The polished round head reduces surface protrusion and enhances the safety of connection and application.
Material: Carriage Bolts are made of 304 stainless steel, the carriage bolts and nuts kit is strong and reliable, resistant to corrode, making them suitable for both indoor and outdoor applications
Well Made Carriage Bolts: All of the stainless steel bolts and hex nuts and flat washers are well manufactured with no burs, smooth-symmetrical head, precise and clean threads
Size: Diameter 3/8 inch, Length 1-1/2 inch-16 UNC Full Course thread Comply with ASME B1.1 standard;there are no issues of thread stuck damaging to compare with nonrust steel bolts in high and low temperature environments.
Requirements of SAE J429/ASTM A307/ASME B18.2.6 for material,mechanics,dimensional inspection level to make sure the bolt and nut have much more strength,duraility, and reliability; ASTM F1941/ASME B18.18.2M/ASTM B117 surface treatment with SC2 to SC...
Nylon Insert Hex Lock Nut have more strong and long lifetime,full course for thread clamping force to avoid loose on vibriation,shocking,earthquake situation; large size flat washer apply for much more worse work conditions.
Square neck underneath the round head feature as suit for their self-locking when position in square hole for nut tighting; Bolt, Nut and flat washer pack up together as one unit for conviences to end user with easy installation experiences.
Size: Diameter 1/2 inch, Length 2-1/2 inch-13 pitch. Material: Made of high quality low carbon steel and color Galvanization to make Carriage bolts much more strength and Antirust. there are no issues of thread stuck damaging to compare with nonrust steel...
Bolt, Nut and flat washer pack up together as one unit for conviences to end user with easy installation experiences.
Nylon Insert Hex Lock Nut have more strong and long lifetime,full course for thread clamping force to avoid loose on vibriation,shocking,earthquake situation; large size flat washer apply for much more worse work conditions.
Square neck underneath the round head feature as suit for their self-locking when position in square hole for nut tighting.
Size: Diameter 3/8 inch, Length 2 inch-16 UNC Full Course thread Comply with ASME B1.1 standard;there are no issues of thread stuck damaging to compare with nonrust steel bolts in high and low temperature environments.
Requirements of SAE J429/ASTM A307/ASME B18.2.6 for material,mechanics,dimensional inspection level to make sure the bolt and nut have much more strength,duraility, and reliability; ASTM F1941/ASME B18.18.2M/ASTM B117 surface treatment with SC2 to SC...
Nylon Insert Hex Lock Nut have more strong and long lifetime,full course for thread clamping force to avoid loose on vibriation,shocking,earthquake situation; large size flat washer apply for much more worse work conditions.
Square neck underneath the round head feature as suit for their self-locking when position in square hole for nut tighting; Bolt, Nut and flat washer pack up together as one unit for conviences to end user with easy installation experiences.
【Size and Package】: 10pcs 1/4"-20 x2" Carriage Bolts ,10pcs 1/4"-20 Hex Nuts,10pcs Flat Washers,10pcs Spring Lock Washers,40pcs square neck bolts set are packaged in a transparent and sturdy plastic box.
【Quality Material】-- Carriage bolts screws Hex nuts Flat washers Spring washers all are made from corrosion-resistant 304 stainless steel, Galvanizing by dipping made them have a tight, uniform, and thick silver zinc coating on surface,Has excellent...
【Excellent combination】-- Carriage bolts’s head are smooth and shiny,Screwdriver cannot work on the bolt head, which has anti-theft effect. Bolts neck is square shaped, can be clamped onto the hole to fix the bolt, making it easy to tighten the nut...
【Wide Use】--Carriage bolt sets are commonly used in machinery, ships, building construction, furniture maintenance, and other scenarios that require high corrosion resistance, strength, and safety, such as heavy equipment, excavators...
Last update on 2026-10-16 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Square-Neck Bolt Lock Washers
Material
Steel: Most common and offers good strength and durability for general use. Look for plated steel (like zinc or cadmium) for corrosion resistance.
Stainless Steel: Ideal for environments prone to rust or moisture, offering superior corrosion resistance.
Size and Fitment
Bolt Diameter: The inner diameter of the lock washer should match the bolt's diameter. Common sizes correspond to standard bolt sizes (e.g., 1/4 inch, 3/8 inch, 1/2 inch).
Washer Thickness: Thicker washers may provide more resistance to loosening but can add bulk. Ensure the washer is compatible with your existing hardware.
Application
Vibration Resistance: For high-vibration environments, consider heavier-duty or specialized designs that offer enhanced locking capabilities.
Environmental Factors: If the application involves extreme temperatures or corrosive substances, opt for materials like stainless steel or specialized coatings.
Frequently Asked Questions
What is the purpose of a square-neck bolt lock washer?
These washers are designed to prevent nuts and bolts from loosening under vibration or thermal cycling. The square neck digs into the surface, providing a locking action that resists rotation.
How do I determine the correct size washer?
The correct size is determined by the diameter of the bolt or screw it will be used with. The inner diameter of the lock washer should closely match the bolt's nominal size.
Can I reuse lock washers?
While some may be reusable, it's generally recommended to use new lock washers for critical applications. Repeated use can reduce their effectiveness and ability to provide a secure lock.
Are there different types of square-neck lock washers?
Yes, they primarily vary in material (steel, stainless steel), plating for corrosion resistance, and thickness. Some may also have slightly different neck designs for specific applications.
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