304 A2-70 Stainless Steel Flat Hex Thin Jam Nut DIN439 GB6172 M2–M16

304 A2-70 Stainless Steel Flat Hex Thin Jam Nut — DIN439 GB6172 M2–M16

DIN439 / GB6172 thin hex jam nuts (also called half nuts or check nuts) are approximately half the height of a standard DIN934 hex nut, making them the correct choice for jam locking (locking two nuts against each other), fine position adjustment on threaded rod, and applications where nut height is restricted. The A2-70 304 stainless steel construction provides corrosion resistance for electronics, outdoor, and industrial applications across the full M2–M16 size range.

Key Specifications

Why Choose DIN439 Thin Jam Nuts?

• Half-height profile — approximately 50% thinner than DIN934 standard hex nut; fits in restricted height applications and reduces assembly stack height
• Jam locking — tighten against a standard hex nut to create a jam lock that resists vibration loosening without a separate lock washer or nyloc insert
• Fine position adjustment — thin profile allows precise position setting on threaded rod and adjustable assemblies
• A2-70 304 stainless — corrosion-resistant for electronics, outdoor, and industrial applications
• Wide M2–M16 range — covers miniature electronics (M2–M3) through structural and architectural assembly (M12–M16)

Typical Applications

• Jam locking on threaded rod and adjustable assemblies (paired with standard DIN934 hex nut)
• Adjustable height feet and leveling pads on machinery and equipment (M8–M16)
• 3D printer Z-axis leadscrew anti-backlash nut locking (M5, M6)
• Electronics enclosure panel nut where height is restricted (M2–M6)
• CNC machine ballscrew and linear guide preload adjustment (M6–M12)
• Architectural threaded rod and tension rod assemblies (M10–M16)

Compatible With

• Standard metric coarse thread bolts, studs, and threaded rod M2–M16
• DIN934 standard hex nuts (for jam locking)
• Spanner / socket: M2=4mm, M3=5.5mm, M4=7mm, M5=8mm, M6=10mm, M8=13mm, M10=17mm, M12=19mm, M14=22mm, M16=24mm AF

Package Contents

• DIN439 thin hex jam nuts in selected size and quantity (per variant)

Frequently Asked Questions

Q: How do I use a jam nut to lock a bolt?

A: Thread a standard hex nut (DIN934) to the desired position. Then thread the jam nut (DIN439) against it and tighten both nuts against each other using two spanners simultaneously. The opposing forces between the two nuts create a jam lock that resists vibration loosening.

Q: What is the height of a DIN439 jam nut compared to a DIN934 hex nut?

A: DIN439 jam nut heights: M3=1.8mm, M4=2.2mm, M5=2.7mm, M6=3.2mm, M8=4.0mm, M10=5.0mm, M12=6.0mm. DIN934 standard hex nut heights: M3=2.4mm, M4=3.2mm, M5=4.0mm, M6=5.0mm, M8=6.5mm, M10=8.0mm, M12=10.0mm. Jam nuts are approximately 40–50% thinner.

Q: Can a jam nut be used alone without a standard nut?

A: Yes. A jam nut can be used as a standalone nut in applications where height is restricted. However, its reduced height means less thread engagement and lower clamping force than a standard hex nut. For structural applications, use a standard DIN934 hex nut instead.