# item.guide
Side-by-Side Comparison Metric Threads (ISO)

M1.6 Thread vs. M3 Thread

Comparing 2 standards across 8 specifications. 8 key differences identified.

Comparing:
M1.6 Thread
M3 Thread

M1.6 is a miniature ISO metric machine screw thread with a nominal major diameter of 1.6 mm and a standard coarse pitch of 0.35 mm. Requiring a 1.25 mm tap drill, it is the standard fastening thread for precision optical equipment, wristwatches, and micro-electronic assemblies.

View full M1.6 Thread spec sheet →

M3 is an ISO metric machine screw thread with a nominal major diameter of 3.0 mm and a standard coarse pitch of 0.50 mm. Requiring a 2.50 mm tap drill, it is the world's most widely deployed fastener in 3D printers, consumer electronics, and PC 5.25-inch optical drive bays.

View full M3 Thread spec sheet →

Specification Comparison Table

8 Parameters
Parameter / Spec
Nominal Major Diameter
1.60 mm 3.00 mm
Standard Coarse Pitch
0.35 mm 0.50 mm
Fine Pitch (Optional)
0.20 mm 0.35 mm
Tap Drill Diameter
1.25 mm (75% thread engagement) 2.50 mm (75% thread engagement)
Minor Diameter (Internal)
1.221 mm 2.459 mm
Tensile Stress Area
1.27 mm² 5.03 mm²
Thread Profile Angle
60 degrees
Common Drive Size
PH1 / PH2 / 2.5mm Allen / T10