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Metal Inserts Put Reusable Threads in Plastic Parts

SI inserts from PennEngineering permanently install in plastic assemblies to provide durable and reusable metal threads for mating hardware and allow for repeated disassembly and re-attachment whenever required. The inserts enable and easy access to an assembly, unlike more permanent fasteners such as adhesives or rivets. Repeated reuse will not damage the brass or lead-free stainless steel and aluminum inserts. Inserts can be ultrasonically pressed and/or heat staked, molded-in during the injection molding process, or cold pressed into a pre-molded or drilled hole, depending on the type of insert used. The inserts can be specified in unified or metric thread sizes and in a variety of designs and lengths, including SI microPEM inserts with threads as small as M1.

Detailed specifications, fastener drawings, 3D models, and performance data (Bulletin SI) for these RoHS-compliant fasteners can be viewed and downloaded for free at

Applications include consumer electronics (wearables, smart phones, and handheld devices) and plastic equipment or components for the medical, automotive, aerospace, transportation, and recreational industries, among many others.

PennEngineering, 1-800-237-4736.

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