4 mm Wire Extension Springs Reference Data: 13 catalog-backed reference configurations are available for sizing review. Use the ranges below to compare the starting envelope before submitting a drawing for final quotation.
- Wire diameter
- 4-4 mm (0.1575-0.1575 in)
- Outside diameter
- 20.79-48.3 mm (0.8185-1.9016 in)
- Inside diameter
- 12.79-40.3 mm (0.5035-1.5866 in)
- Free length
- 59.13-271.93 mm (2.328-10.7059 in)
- Spring rate
- 0.937-27.122 N/mm
- Maximum load
- 21.03-567.11 N
Catalog rows are reference configurations for custom design review. Final dimensions, loads, tolerances and material certifications are confirmed during quotation.
Products Represented in This Data
These rows show which product designs are represented in the reference data. Open the matching product for geometry, quotation inputs, application guidance and RFQ details.
- English-Hook Extension Springs3 matching rowsEnglish-Hook Extension Springs Application Guide
- German-Hook Extension Springs3 matching rowsGerman-Hook Extension Springs Application Guide
- Offset-Hook Extension Springs2 matching rowsOffset-Hook Extension Springs Application Guide
- Round-Hook Extension Springs5 matching rowsRound-Hook Extension Springs Application Guide
Related Spring Design Guides
Use these guides to define the working dimensions, loads and quotation requirements.
Sizing Overview
4 mm Wire extension springs pages are useful when the available wire diameter is fixed and the outside diameter, free length or load target needs to be adjusted. The rows below combine multiple extension springs product forms so you can compare nearby options before an RFQ review.
- Wire diameter
- 4-4 mm (0.1575-0.1575 in)
- Outside diameter
- 20.79-48.3 mm (0.8185-1.9016 in)
- Inside diameter
- 12.79-40.3 mm (0.5035-1.5866 in)
- Free length
- 59.13-271.93 mm (2.328-10.7059 in)
- Spring rate (N/mm)
- 0.937-27.122 N/mm
- Maximum load (N)
- 21.03-567.11 N
Matching Reference Configurations
| Model | Product | Wire / thickness | OD | ID | Free length | Rate (N/mm) | Material | Max load (N) |
|---|---|---|---|---|---|---|---|---|
| SE-400-0208-1132-0432 | Round-Hook Extension Springs | 4 mm | 20.79 mm | 12.79 mm | 113.15 mm | 27.122 | 316 Stainless Steel | 567.11 |
| SE-400-0295-0591-0508 | German-Hook Extension Springs | 4 mm | 29.52 mm | 21.52 mm | 59.13 mm | 24.143 | Oil-Tempered Spring Wire (SWO) | 237.03 |
| SE-400-0315-1736-0435 | Offset-Hook Extension Springs | 4 mm | 31.52 mm | 23.52 mm | 173.61 mm | 1.925 | Phosphor Bronze (QSn4-0.3) | 62.69 |
| SE-400-0334-2719-0590 | Round-Hook Extension Springs | 4 mm | 33.39 mm | 25.39 mm | 271.93 mm | 1.824 | Music Wire (SWP-A) | 108.34 |
| SE-400-0364-1006-0506 | English-Hook Extension Springs | 4 mm | 36.43 mm | 28.43 mm | 100.63 mm | 4.559 | 316 Stainless Steel | 97.2 |
| SE-400-0367-2126-0460 | German-Hook Extension Springs | 4 mm | 36.74 mm | 28.74 mm | 212.59 mm | 1.502 | 304 Stainless Steel | 57.41 |
| SE-400-0395-1513-0527 | Round-Hook Extension Springs | 4 mm | 39.49 mm | 31.49 mm | 151.27 mm | 2.192 | Oil-Tempered Spring Wire (SWO) | 58.04 |
| SE-400-0397-2198-0522 | English-Hook Extension Springs | 4 mm | 39.67 mm | 31.67 mm | 219.82 mm | 1.344 | Music Wire (SWP-B) | 52.91 |
| SE-400-0402-1462-0504 | German-Hook Extension Springs | 4 mm | 40.22 mm | 32.22 mm | 146.23 mm | 1.303 | Beryllium Copper (QBe2) | 26.38 |
| SE-400-0425-0793-0484 | English-Hook Extension Springs | 4 mm | 42.48 mm | 34.48 mm | 79.28 mm | 2.567 | Beryllium Copper (QBe2) | 37.18 |
| SE-400-0432-2233-0569 | Offset-Hook Extension Springs | 4 mm | 43.23 mm | 35.23 mm | 223.32 mm | 0.937 | 60Si2MnA Spring Steel | 46.74 |
| SE-400-0470-0707-0431 | Round-Hook Extension Springs | 4 mm | 46.96 mm | 38.96 mm | 70.69 mm | 4.001 | Music Wire (SWP-B) | 47.07 |
| SE-400-0483-1628-0499 | Round-Hook Extension Springs | 4 mm | 48.3 mm | 40.3 mm | 162.83 mm | 0.96 | Oil-Tempered Spring Wire (SWO) | 21.03 |
Quotation Notes
For a final quote, send the target load or spring rate, working travel, material preference, operating temperature, environment, quantity and drawing. CustomSprings can adjust coil count, end type, free length, outside diameter and surface finish from these reference rows.
CustomSprings Engineering Catalog
Request This Spring
Send your dimensions, quantity and drawing for engineering review.
Frequently Asked Questions
Can the outside diameter change if the wire diameter stays fixed?
Yes. Outside diameter, coil count, free length and end type can be changed around the selected wire diameter if the stress, solid height and load target remain feasible.
Are the dimensions shown in millimeters or inches?
The catalog data is stored in millimeters. The summary also gives inch conversions for quick review by US customers.
What information is needed for a quote?
Send the wire diameter, OD or ID, free length, rate or load, working travel, material, environment, quantity and drawing.