Filter by
Drive Style
Fastener Head Type
Rounded Head Style
Material
System of Measurement
Threading
Finish
Hardness
Export Control Classification Number (ECCN)
DFARS Specialty Metals
Tensile Strength
Rounded Head Profile
Thread Direction
Thread Fit
Shank Type
Overall Diameter
About Rounded Head Screws
More
Tamper-Resistant Tri-Groove Rounded Head Screws
Difficult to remove without special tools, these screws have three grooves. For installation tools, see Tri-Groove bits and drivers. Screws are zinc plated for corrosion resistance in wet environments. Length is measured from under the head.
For technical drawings and 3-D models, click on a part number.
| Lg. | Threading | Min. Thread Lg. | Head Dia. | Head Ht. | Drive Size | Tensile Strength, psi  | Pkg. Qty. | Pkg. | |
Zinc-Plated Steel | |||||||||
|---|---|---|---|---|---|---|---|---|---|
6-32 | |||||||||
| 3/8" | Fully Threaded | __ | 0.26" | 0.12" | No. 6 | 80,000 | 50 | 000000000 | 000000 |
| 1/2" | Fully Threaded | __ | 0.26" | 0.12" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
| 3/4" | Fully Threaded | __ | 0.26" | 0.12" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
8-32 | |||||||||
| 3/8" | Fully Threaded | __ | 0.28" | 0.148" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
| 1/2" | Fully Threaded | __ | 0.28" | 0.148" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
| 3/4" | Fully Threaded | __ | 0.28" | 0.148" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
| 1" | Fully Threaded | __ | 0.28" | 0.148" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
| 1 1/4" | Fully Threaded | __ | 0.28" | 0.148" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
| 1 1/2" | Fully Threaded | __ | 0.28" | 0.148" | No. 6 | 80,000 | 50 | 000000000 | 00000 |
10-24 | |||||||||
| 1/2" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 3/4" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 1" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 25 | 000000000 | 0000 |
| 1 1/2" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 25 | 000000000 | 0000 |
10-32 | |||||||||
| 1/2" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 3/4" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 1" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 1 1/2" | Fully Threaded | __ | 0.375" | 0.15" | No. 10 | 80,000 | 25 | 000000000 | 0000 |
1/4"-20 | |||||||||
| 1/2" | Fully Threaded | __ | 0.375" | 0.155" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 3/4" | Fully Threaded | __ | 0.375" | 0.155" | No. 10 | 80,000 | 50 | 000000000 | 00000 |
| 1" | Fully Threaded | __ | 0.375" | 0.155" | No. 10 | 80,000 | 25 | 000000000 | 0000 |
| 1 1/2" | Fully Threaded | __ | 0.375" | 0.155" | No. 10 | 80,000 | 25 | 000000000 | 0000 |
| 2" | Fully Threaded | __ | 0.375" | 0.155" | No. 10 | 80,000 | 25 | 000000000 | 00000 |
| 2 1/2" | Partially Threaded | 1 1/2" | 0.375" | 0.155" | No. 10 | 80,000 | 10 | 000000000 | 0000 |
5/16"-18 | |||||||||
| 5/8" | Fully Threaded | __ | 0.57" | 0.275" | No. 20 | 80,000 | 25 | 000000000 | 00000 |
| 3/4" | Fully Threaded | __ | 0.57" | 0.275" | No. 20 | 80,000 | 25 | 000000000 | 00000 |
| 1" | Fully Threaded | __ | 0.57" | 0.275" | No. 20 | 80,000 | 25 | 000000000 | 00000 |
Tri-Groove Bits
Grip the indentations on the head of tri-groove fasteners. These bits have a groove in the shank to fit directly into power tools without an adapter.
For technical drawings and 3-D models, click on a part number.
Overall | |||||
|---|---|---|---|---|---|
| For Screw Size | Lg. | Dia. | Material | Each | |
1/4" Hex Shank Size for Power Tools | |||||
| No. 1, No. 2, No. 3, No. 4 | 1 3/8" | 3/8" | Steel | 0000000 | 000000 |
| No. 5, No. 6, No. 7, No. 8, No. 9, No. 10, No. 11 | 1 1/4" | 1/2" | Steel | 0000000 | 00000 |
| No. 8, No. 9, No. 10, No. 11, No. 12, 1/4" | 1 1/4" | 7/8" | Steel | 0000000 | 00000 |
| No. 12, 5/16" | 1 1/4" | 3/4" | Steel | 0000000 | 00000 |
Tri-Groove Bit Sets
Grip the indentations on the head of tri-groove fasteners. These bits have a groove in the shank and fit directly into power tools without an adapter.
| Components Included | Bits Included | Material | Bit Material | Container Type | Each | |
1/4" Hex Shank Size for Power Tools | ||||||
|---|---|---|---|---|---|---|
| 4 Bits | Tri-Groove: 0.375" O'all Dia. for No. 1-No. 8 (1 3/8" O'all Lg.) Tri-Groove: 0.5" O'all Dia. for No. 5-No. 11 (1 1/4" O'all Lg.) Tri-Groove: 0.75" O'all Dia. for No. 12-No. 13, 5/16" (1 1/4" O'all Lg.) Tri-Groove: 0.875" O'all Dia. for No. 8-No. 12, 1/4" (1 1/4" O'all Lg.) | Steel | High-Speed Steel | Plastic Pouch | 0000000 | 000000 |