Side-by-Side Comparison
Imperial Threads (UNC/UNF)
#10-24 UNC vs. 3/8"-16 UNC
Comparing 2 standards across 9 specifications. 9 key differences identified.
Comparing:
#10-24 UNC
3/8"-16 UNC
10-24 UNC is a numbered Unified Coarse machine screw thread with a major diameter of 0.1900 inches (4.826 mm) and 24 threads per inch (TPI). Requiring a #25 (0.1495 inch) tap drill, it provides high clamping torque for household appliances, outdoor power equipment, and light mechanical assemblies.
3/8"-16 UNC is a fractional Unified Coarse machine screw thread with a major diameter of 0.3750 inches (9.525 mm) and 16 threads per inch (TPI). Requiring a 5/16 inch (0.3125 inch) tap drill, it is the international standard for professional photography tripod-to-head mounting studs, cinema camera baseplates, and stage microphone stands.
Specification Comparison Table
9 Parameters| Parameter / Spec | ||
|---|---|---|
|
Nominal Major Diameter
|
0.1900 in (4.826 mm) | 0.3750 in (9.525 mm) |
|
Threads Per Inch (TPI)
|
24 TPI (Coarse pitch: 1.058 mm) | 16 TPI (Coarse pitch: 1.588 mm) |
|
Fine Pitch Equivalent
|
#10-32 UNF (0.794 mm pitch — widely used in 19" AV racks) | 3/8"-24 UNF (1.058 mm pitch) |
|
Minor Diameter (Internal)
|
0.1449 in (3.680 mm) | 0.3073 in (7.805 mm) |
|
Tensile Stress Area
|
0.0175 in² (11.3 mm²) | 0.0775 in² (50.0 mm²) |
|
Tap Drill Size (UNC)
|
#25 drill bit (0.1495 in / 3.80 mm) | — |
|
Tap Drill Size (#10-32 UNF)
|
#21 drill bit (0.1590 in / 4.04 mm) | — |
|
Recommended Tap Drill Size
|
— | 5/16 in drill bit (0.3125 in / 7.94 mm) |
|
Common Drive Size
|
— | 9/16" Hex (14.28 mm) / 5/16" Allen |