M4 brass inserts for durable threads in plastic parts

These brass flanged expanding inserts are M4 threaded inserts made for plastic components that need a stronger, longer-lasting fastening point. The reversed through-hole design helps create reliable metal threads in parts where direct threading into plastic would wear out more quickly.

Key features of the flanged expanding insert design

• M4 internal thread for use with compatible M4 machine screws and hardware
• Brass construction for good thread durability, corrosion resistance, and repeatable fastening
• Flanged profile to help with positioning and load distribution at the surface of the part
• Reversed through-hole style for applications designed around a through-hole insert configuration
• Pack of 10 for repairs, assemblies, prototypes, and small production jobs

Where these brass inserts are commonly used

These inserts are suited to plastic enclosures, printed jigs, fixtures, machine guards, brackets, and custom assemblies that need a repeatable M4 machine thread. They are especially useful in 3D printed or moulded plastic parts that will be opened for maintenance, adjusted over time, or assembled with standard metric fasteners.

Why metal threaded inserts help in plastic assemblies

Plastic threads can deform or strip when a fastener is tightened repeatedly. A brass insert gives the plastic part a more durable threaded interface, which helps improve serviceability and makes the assembly better suited to repeated use.