Compression Spring A2 Stainless Steel WireDia.=0.5mm OD=3mm~5mm Y Type Spring

Match the OD to your guide bore or guide rod. For a bore-guided application, the spring OD should be slightly smaller than the bore ID (typically 0.1–0.3 mm clearance). For a rod-guided application, the spring ID should be slightly larger than the rod OD. The ID of these springs is approximately OD minus twice the wire diameter (e.g., 3 mm OD – 2×0.5 mm = 2 mm ID).

Choose a free length that is longer than your required working length. A common rule of thumb is to select a spring whose free length is 20–30% longer than the compressed working length, so the spring operates within its elastic range and does not bottom out. For example, if your mechanism compresses the spring to 10 mm, a free length of 12–15 mm is a reasonable starting point.

With a 0.5 mm wire diameter, these are light-duty springs suited for low-force applications such as switch returns, sensor contacts, and small latching mechanisms. The exact spring rate (N/mm) depends on the OD and free length of the specific variant. For precise load calculations, please contact us to confirm the spring rate for your chosen size.

A2 (Grade 304) stainless steel offers good resistance to atmospheric corrosion, humidity, and mild chemical exposure. It is suitable for indoor use, light outdoor enclosures, and applications with occasional moisture contact. For marine environments or exposure to chlorides and strong acids, A4 (Grade 316) stainless steel would be more appropriate.

"Y-Type" refers to the open-coil helical compression spring form — the standard cylindrical coil spring shape used for axial compression loads. The coils are evenly spaced along the length, allowing the spring to compress uniformly. This distinguishes it from conical, barrel, or hourglass spring profiles.

Yes. The fine 0.5 mm wire diameter and small OD (3–5 mm) make these springs well-suited for use in PCB spring contacts, battery compartment contacts, push-button return mechanisms, and miniature sensor housings. The stainless steel material is non-magnetic (austenitic 304), which is advantageous in sensitive electronic environments.

For prototyping or one-off repairs, the 1–10 pcs packs are the most cost-effective entry point. If you are running a small production batch or need spares on hand, the 20–50 pcs packs offer a lower per-unit cost. Check the Size (Qty) variant selector to compare pack options for your chosen OD and length combination.