Stainless Steel Cage Nuts

What is a cage nut & when to use it?

A cage nut is a square nut held in a spring-steel “cage” that clips into a square hole in sheet metal or rack rails.

Use a cage nut when you want:

A strong threaded point in thin sheet / rack rail

The ability to change positions easily (move the nut to another hole)

To mix different thread sizes in the same panel (M5, M6, M8 etc.)

Typical uses:

19″ equipment racks / server racks / network racks

Control panels, enclosures and cabinets with square punched holes

Sheet metal frames where you can’t tap threads due to thin material

Rack / panel system & thread type

First confirm where you’re using the cage nut:

19″ Rack / cabinet rails

Common standard sizes: M5, M6, M8 (metric) or #10-32, 12-24 (imperial)

Most EU/India racks → M6 is the most common for equipment mounting.

Choose thread type based on:

The bolts / rack screws you or your customers already use

The standard in that industry (e.g., M6 for IT/server racks in India)

Rule:

Cage nut thread must match the screw/bolt thread – same diameter & pitch.

Panel thickness & cage style

Cage nuts are made for specific panel/rail thickness ranges (e.g., 1.0–1.5 mm, 1.5–2.5 mm, etc.):

For thin sheet / rack rails

Use cage nuts specified for that thickness range, so the tabs clip firmly and don’t loosen.

Check:

Hole size (usually square) must match cage nut design.

Panel thickness must be within the cage nut’s clamping range.

If panel is too thick or too thin, the cage nut may:

Be difficult to install, or

Sit loose and move during tightening.

Material & corrosion (nut + cage)

You need to consider both the nut and the cage:

Standard option (most common)

Nut: carbon steel, property class 8 or 10, zinc-plated

Cage: spring steel, zinc-plated

Good for indoor racks, IT rooms, electrical panels.

Stainless option (for corrosive / clean environments)

Nut: A2 (304) stainless, sometimes A4 (316) if available

Cage: stainless or coated spring steel

For outdoor cabinets, marine, food, pharma, chemical plants or wash-down environments.

Selection thumb rule:

Normal indoor racks/panels → Zinc-plated steel cage nuts (class 8/10).

Corrosive / outdoor / hygienic → A2 (304) or A4 (316) stainless cage nuts.

Match with same-grade bolts where possible (A2 with A2, etc.).

Mechanical Properties (Guide) – Cage Nuts

Mechanically, the nut follows a standard property class (e.g., 8, 10, A2-70), while the cage is a spring element whose job is to position/retain the nut in the panel.

The joint strength is governed by: nut property class, bolt grade, thread engagement, cage fit, and panel strength.

Carbon Steel Cage Nuts (Zinc-plated)

Nut material: carbon steel, typically property class 8 or 10

Capable of working with class 8.8 or 10.9 screws, depending on nut class.

Cage material: spring steel, zinc-plated for basic corrosion resistance.

Usage:

Indoor racks, IT cabinets, control panels, server/network racks.

Stainless Steel Cage Nuts

Nut material:

A2 (304), property class ~70 (A2-70), or

A4 (316) where available for higher corrosion resistance.

Cage material:

Stainless or coated spring steel, depending on design.

Usage:

Outdoor enclosures, marine/coastal installations, food/pharma/chemical plants, high humidity or aggressive environments.

Key mechanical points:

For carbon steel type:

Property class 8 / 10 nuts with compatible screws can safely handle standard rack mounting loads when used correctly.

For stainless type:

A2-70 / A4-70 nuts provide sufficient strength for most equipment mounting, plus excellent corrosion resistance.