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Thread-Forming Screws for Joining Wood to Metal

Thread-forming screws press threads into drilled holes for a tight vibration-resistant assembly. All are beveled under the head for use in countersunk holes. A Torx drive allows you to apply extra force with less slippage or damage to the recess. They're black-phosphate steel to resist corrosion in dry environments. Length is measured from the top of the head.
For technical drawings and 3-D models, click on a part number.
Head | |||||||||
---|---|---|---|---|---|---|---|---|---|
Lg. | Dia. | Ht. | Drive Size | Drill Bit Size | Threading | Min. Thread Lg. | Pkg. Qty. | Pkg. | |
Black-Phosphate Steel | |||||||||
1/4"-20 | |||||||||
1" | 0.479" | 0.153" | T30 | No. 3 | Fully Threaded | __ | 50 | 000000000 | 000000 |
1 1/4" | 0.479" | 0.153" | T30 | No. 3 | Fully Threaded | __ | 50 | 000000000 | 00000 |
1 1/2" | 0.479" | 0.153" | T30 | No. 3 | Fully Threaded | __ | 50 | 000000000 | 00000 |
1 3/4" | 0.479" | 0.153" | T30 | No. 3 | Fully Threaded | __ | 50 | 000000000 | 00000 |
2" | 0.479" | 0.153" | T30 | No. 3 | Fully Threaded | __ | 50 | 000000000 | 00000 |
2 1/4" | 0.479" | 0.153" | T30 | No. 3 | Partially Threaded | 1 1/2" | 50 | 000000000 | 00000 |
2 1/2" | 0.479" | 0.153" | T30 | No. 3 | Partially Threaded | 1 1/2" | 25 | 000000000 | 00000 |
3" | 0.479" | 0.153" | T30 | No. 3 | Partially Threaded | 1 1/2" | 25 | 000000000 | 00000 |
3 1/2" | 0.479" | 0.153" | T30 | No. 3 | Partially Threaded | 1 1/2" | 10 | 000000000 | 00000 |
4" | 0.479" | 0.153" | T30 | No. 3 | Partially Threaded | 1 1/2" | 10 | 000000000 | 00000 |
5/16"-18 | |||||||||
1 3/4" | 0.6" | 0.191" | T40 | H | Fully Threaded | __ | 25 | 000000000 | 00000 |
2" | 0.6" | 0.191" | T40 | H | Fully Threaded | __ | 25 | 000000000 | 00000 |
2 1/4" | 0.6" | 0.191" | T40 | H | Partially Threaded | 1 1/2" | 10 | 000000000 | 0000 |
2 1/2" | 0.6" | 0.191" | T40 | H | Partially Threaded | 1 1/2" | 25 | 000000000 | 00000 |
3" | 0.6" | 0.191" | T40 | H | Partially Threaded | 1 1/2" | 10 | 000000000 | 00000 |
Rounded Head Screws for Particleboard and Fiberboard

Sharp, angled threads cut into particleboard, medium-density fiberboard (MDF), and hardboard such as masonite without splitting. Black-oxide and black-phosphate steel screws resist corrosion in dry environments. Length is measured from under the head.
For technical drawings and 3-D models, click on a part number.
Head | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Lg. | Dia. | Ht. | Drive Size | Drill Bit Size | Approximate Threads per Inch | Threading | Min. Thread Lg. | Pkg. Qty. | Pkg. | |
Black-Phosphate Steel | ||||||||||
No. 8 | ||||||||||
1/2" | 0.322" | 0.096" | No. 2 | 5/64" | 8 | Partially Threaded | 0.33" | 100 | 000000000 | 00000 |
1 1/4" | 0.322" | 0.096" | No. 2 | 5/64" | 9 | Partially Threaded | 0.825" | 100 | 000000000 | 0000 |
1 3/4" | 0.322" | 0.096" | No. 2 | 5/64" | 10 | Partially Threaded | 1.155" | 100 | 000000000 | 0000 |
2" | 0.322" | 0.096" | No. 2 | 5/64" | 9 | Partially Threaded | 1.32" | 100 | 000000000 | 0000 |
Thread-Forming Small-Head Screws for Softwood and Plastic-Wood Composites

Thread-forming screws press threads into drilled holes for a tight, vibration-resistant assembly. Also known as trim-head deck screws, they have a small flat head and slender shank to reduce the risk of splitting. The sharp point and narrow body penetrates softwood and plastic-wood composite decking material. Made from steel, they have a black-phosphate finish to resist corrosion in wet environments. Length is measured from the top of the head.
For technical drawings and 3-D models, click on a part number.
Head | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Lg. | Dia. | Ht. | Drive Size | Drill Bit Size | Approximate Threads per Inch | Threading | Min. Thread Lg. | Pkg. Qty. | Pkg. | |
Black-Phosphate Steel | ||||||||||
No. 6 | ||||||||||
1 5/8" | 0.224" | 0.135" | No. 1 | 1/16" | 18 | Partially Threaded | 13/16" | 100 | 000000000 | 000000 |
2 1/4" | 0.224" | 0.135" | No. 1 | 1/16" | 18 | Partially Threaded | 1 1/8" | 100 | 000000000 | 00000 |
No. 8 | ||||||||||
3" | 0.264" | 0.155" | No. 2 | 5/64" | 15 | Partially Threaded | 1 1/2" | 50 | 000000000 | 00000 |
High-Hold Screws for Joining Drywall to Wood

Alternating high and low threads minimize driving torque and allow the screw to hold more material between threads for a stronger hold and better strip-resistance than standard drywall screws for wood. A curved neck sinks into drywall without tearing the paper surface. These screws are black-phosphate steel to resist corrosion in dry environments. Length is measured from the top of the head.
For technical drawings and 3-D models, click on a part number.
Head | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Lg. | Dia. | Ht. | Drive Size | Max. Drilling Thick. | Approximate Threads per Inch | Threading | Min. Thread Lg. | Pkg. Qty. | Pkg. | |
Black-Phosphate Steel | ||||||||||
No. 6 | ||||||||||
1" | 0.334" | 0.031" | No. 2 | 0.036" | 18 | Fully Threaded | __ | 100 | 000000000 | 00000 |
1 1/4" | 0.334" | 0.031" | No. 2 | 0.036" | 18 | Fully Threaded | __ | 100 | 000000000 | 0000 |
1 5/8" | 0.334" | 0.031" | No. 2 | 0.036" | 18 | Fully Threaded | __ | 100 | 000000000 | 0000 |
2" | 0.334" | 0.031" | No. 2 | 0.036" | 18 | Fully Threaded | __ | 100 | 000000000 | 0000 |
2 1/4" | 0.334" | 0.031" | No. 2 | 0.036" | 18 | Fully Threaded | __ | 100 | 000000000 | 0000 |
No. 8 | ||||||||||
2 1/2" | 0.334" | 0.039" | No. 2 | 0.036" | 18 | Fully Threaded | __ | 100 | 000000000 | 00000 |
3" | 0.334" | 0.039" | No. 2 | 0.036" | 18 | Partially Threaded | 2" | 100 | 000000000 | 00000 |