RS PRO, M3 Brass Threaded Insert diameter 4mm Depth 4.78mm

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Subtotal (1 bag of 100 units)*

$59.53

(exc. GST)

$68.46

(inc. GST)

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  • 491 unit(s) ready to ship from another location
  • Plus 6 unit(s) shipping from 08 December 2025
  • Plus 9 unit(s) shipping from 23 January 2026
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5 +$49.00$0.49

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RS Stock No.:
278-584
Brand:
RS PRO
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Brand

RS PRO

Thread Size

M3

Fixing Hole Diameter

4mm

Body Outside Diameter

4.22mm

Body Depth

4.78mm

Material

Brass

Thickness of Material Minimum

6.2mm

Expansion Inserts


A range of expansion inserts suitable for use with most plastic materials, using either through or blind holes. Knurled outer diameter with expansion slots prevent rotation or loosening due to vibration and ensures consistent self-locking pressure on the fixing screws

Features and Benefits:


Use in drilled or moulded-in holes
Install by simple press or hammer-in methods

Available with Flush Head (RS 278-534, RS 278-540, RS 278-556, RS 278-562, RS 278-578)
Available with Flange Head (RS 278-584, RS 278-590, RS 278-607, RS 278-613, RS 278-629)

Typical Applications:


Threaded inserts are available in various materials and finishes and metric course threads to suit every application. Expansion inserts are ideal for plastics which can resist the expansion of the insert but also flexible to let the knurls anchor into the material. Threaded expansion inserts are designed to provide strong reusable threads in thermoset and other hard plastics and are commonly used in plastic casings and housing.

RS PRO
RS PRO is our own brand range and brings you a wide range of high-quality, great value products offering you more choice. Trusted by engineers all over the world, every part of every RS PRO product has been rigorously tested against demanding industry standards; they’re only given the RS PRO Seal of Approval if we’re confident of their exceptional quality, which means you can be confident too.

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