Product: Tension (Extension) Spring — 65Mn spring steel Why choose these springs Reliable pulling force and rebound: Designed to store and release mechanical energy for tension applications. Durable construction: Made from 65Mn spring steel for strong elasticity and good fatigue resistance in typical mechanical uses. Multiple size options: Choose the exact wire, outer diameter, and length to match your device for a precise fit. Pack sizes for repairs or projects: Available in packs of 2 or 5 to cover single replacements or small assemblies. Key attributes Name: Tension Spring / Extension Spring Material: Spring steel (65Mn) Surface treatment: Untreated (raw finish) Quantity options: 2 Pcs or 5 Pcs per package Available sizes: Wire diameter: 0.5 mm or 0.8 mm Outer diameter: 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm length: 20 mm up to 120 mm (select required length within this range) How it solves common problems Accurate replacements: Multiple diameter and length options let you match worn or broken springs exactly, restoring original function without modifications. Consistent performance: 65Mn spring steel delivers predictable elasticity for mechanisms that depend on stable tension. Ready for finishing: Untreated surface gives flexibility to add your preferred coating or plating for corrosion protection or appearance. Choosing the right spring Match three dimensions: Verify wire diameter, outer diameter, and length against your existing spring or design requirements. Consider environment: Untreated finish can be left asis for indoor or dry locations; apply a coating (plating, paint, or oil) if corrosion resistance is required. Pack size: Select 2 Pcs for individual replacements or 5 Pcs for small projects, spares, or assemblies. Typical applications (practical examples) Small mechanical repairs: broken extension springs in household appliances, tools, or hobby equipment where size and tension must match precisely. Prototype and DIY projects: Use in small mechanisms, linkage systems, and action devices during design iterations where multiple sizes may be tested. Model and electronics assemblies: Install in radiocontrolled vehicles, model kits, or small actuators that require compact, reliable tension springs. What to expect A directfit mechanical spring available in specified wire diameters, outer diameters, and lengths. Untreated 65Mn steel construction — strong and elastic, but may require finishing for longterm corrosion protection depending on use conditions. Packaged in sets of 2 or 5 for immediate replacement or smallbatch use. If you need help selecting the correct size, measure the original spring's wire diameter, outer diameter, and length, then choose the matching options from the listed sizes.