If you are searching for 1/2-inch bolts, the right choice depends on the thread, length, material, and application. The Prime-Line A307 bolt is a versatile option for standard fastening, while the galvanized Hicarer lag screws are designed for wood. Choose the stainless options for corrosion resistance, and note that the 1/4-inch kit below is not a substitute for a 1/2-inch bolt.
| Product | Best For | Key Detail |
|---|---|---|
| Prime-Line A307 Hex Bolts | General fastening | 1/2-13, 1-1/2-inch length |
| Hicarer Lag Screw Kit | Wood projects | 1/2-inch diameter, 10-inch length |
| Stainless 1/2-13 Hex Bolts | Corrosion resistance | 304 stainless steel, 1-inch length |
| Grade 5 Fine Hex Cap Screws | Fine-thread fastening | 1/2-20, 1-1/2-inch length |
| BNUOK 1/4-20 Bolt Kit | Smaller fasteners | Not a 1/2-inch bolt |
Prime-Line A307 Zinc-Plated Hex Bolts
These bolts measure 1/2-13 by 1-1/2 inches and are made from A307 Grade A zinc-plated steel. The product is supplied in a 25-pack. The listing describes them as a common, versatile fastener for use with a nut or a threaded hole of the same diameter and thread size.
Best for: Buyers who need multiple standard 1/2-13 hex bolts for general fastening. This is the most straightforward choice when the project calls for the stated diameter, thread, and length.
Limitation: The listing specifies zinc-plated steel, not stainless steel, and does not describe these as wood lag screws.
Hicarer Galvanized Wood Lag Screw Kit
This kit contains 60 lag screws and 60 flat washers. Each screw is listed as 1/2 inch in diameter and 10 inches long, with a hot-dip galvanized surface. The listing describes the threaded design as intended to help secure wood and says the washers have a 1-3/8-inch outside diameter.
Best for: Wood projects that call for long, large-diameter lag screws and included washers. Choose this instead of a conventional hex bolt when the job specifically calls for a lag-style wood fastener.
Limitation: A wrench is not included. Confirm the required screw length and fastening method for the project before choosing this kit.
304 Stainless 1/2-13 Hex Bolt
This five-piece set contains fully threaded 304 stainless steel hex bolts. The listed size is 1/2-13 by 1 inch, with a 0.74-inch head diameter and 0.307-inch head height. The product description identifies the material as 18-8 stainless steel.
Best for: Buyers who need a shorter 1/2-13 bolt and prefer stainless steel. Compare its one-inch length with the required length measured from beneath the head.
Limitation: The listing describes a five-piece set and a one-inch length; it is not the right option if the project requires a longer bolt or another thread pitch.
Grade 5 Fine-Thread Hex Cap Screws
This five-piece pack contains steel Grade 5 fine hex cap screws sized 1/2-20 by 1-1/2 inches. The 20 threads per inch distinguish these from the 1/2-13 coarse-thread bolts elsewhere in this list.
Best for: Buyers whose project specifically requires a 1/2-20 fine thread and a 1-1/2-inch screw length. Match the thread to the nut or threaded hole rather than relying on diameter alone.
Limitation: The listing identifies the material as steel but does not specify a coating. Do not select it as a stainless-steel option based on the available product details.
BNUOK Stainless 1/4-20 Bolt Kit
This 18-set kit includes 1/4-20 by 1/2-inch hex bolts, nylon-insert lock nuts, flat washers, and lock washers. The parts are listed as 304 stainless steel, and the bolts are fully threaded. The product description also states that the set meets ASME B 18.2.1 specifications.
Best for: Buyers who need a smaller 1/4-inch fastener kit with matching nuts and washers. It may suit a related project, but it is not a 1/2-inch bolt.
Limitation: The bolt diameter is 1/4 inch, so avoid this kit if your specifications call for a 1/2-inch diameter.
Buying Guide
What does “1/2-inch bolt” mean?
For these products, 1/2 inch refers to the nominal diameter, not the bolt length. Check the complete size: for example, 1/2-13 x 1-1/2 means a 1/2-inch diameter, 13 threads per inch, and a 1-1/2-inch length. Confirm how length is measured for the fastener type; the stainless bolt listing measures from under the head.
Should you choose coarse or fine threads?
The Prime-Line and stainless hex bolts are listed as 1/2-13, while the Grade 5 cap screws are 1/2-20. These thread pitches are not interchangeable. Match the bolt to the nut or threaded hole, and verify pitch as well as diameter.
When is a lag screw the better choice?
Choose the Hicarer product when you need a long lag-style fastener for a wood application. Its listed length is 10 inches, unlike the shorter conventional hex bolts. Confirm that a lag screw is appropriate for the material and connection; do not treat it as interchangeable with every bolt.
Which material and pack size should you compare?
Stainless steel is specified for the 304 stainless options, while the other listings identify zinc-plated or hot-dip galvanized steel, or simply steel. Compare the stated material and finish with the project environment. Also check quantity: listings range from five-piece packs to a 25-pack or 60-screw kit.
Frequently Asked Questions
Are 1/2-13 and 1/2-20 bolts interchangeable?
No. They have different thread pitches. Use the thread pitch required by the matching nut or threaded hole.
Is a 1/2-inch bolt 1/2 inch long?
No. The 1/2-inch measurement refers to nominal diameter. Length is specified separately, such as 1 inch or 1-1/2 inches.
Which option is intended for wood?
The Hicarer kit is described as a wood lag screw kit and includes 1/2-inch-diameter, 10-inch-long screws and flat washers.
Does the BNUOK kit contain 1/2-inch bolts?
No. Its bolts are 1/4-20 by 1/2 inch. In that size, 1/2 inch is the bolt length, not its diameter.