Springmasters Stock Extension Springs

Resistive force springs

Extension springs, also known as tension springs, apply a resistive force as the spring extends and are commonly utilised to move or return a component part. Extension springs require special ends to permit application of the load and these ends assume many forms.

Manufacture and stockist

We manufacture and stock extension springs, see the below categories and choose from the different wire diameter sizes available. Use the filter options on teh category page to find your required Extension Spring, or if you know the product code enter it on the ‘search Part No. box at the top of the page.

Taking quality control seriously

Our team of engineers and quality control personnel monitor each stage of the production of compression springs, using both computer and manual SPC systems, to ensure that this aim is achieved.

Spring Specification

  • Ends: German loops, random position
  • Note: All Springmasters Extension Springs are right hand coiled.
  • Tolerances: All dimensions and forces conform to DIN 2095 (Grade 2) or BS 1726 Class B.


  • Music Wire to DIN 17223, Class C. No.1.1200 or BS 1408 CR3.
  • Stainless Steel Wire to DIN 17224, No.1.14310 or BS 2056 302S26.

Surface Finish

  • Music Wire = Oiled
  • Stainless Steel = Self

Recommended Working Temps

  • Music Wire = 120°C (max.)
  • Stainless Steel = 300°C (max.)

standard extension springs

Stock Extension Springs

Wire Dia (0.18mm-5.00mm)

Extension springs with wire diameters between 0.18mm and 5.00mm are available in music wire and stainless steel. Filter our stock list via wire diameter, outside diameter, free length and rate (N/mm).

12 inch extension sprngs

12″ extension springs, ranging from an outside diameter of 0.092 inch to 1 inch in both stainless steel and cardon steel. Filter our stock via outside diameter, inside diameter and approximate number of coils

1 metre long extension spri

1 meter long extension springs are available in carbon steel and stainless steel. Filter our stock list via wire diameter and outside diameter.

BespokeExtension Springs

Springmasters also offer bespoke spring design and manufacture, click below to learn more or enter your specifications to request a custom spring quote.

Information for students and graduates.

We are starting to locate and collate a list of educational resources which we feel would be very useful to budding engineers and springmakers alike.

Please contact us if you are aware of an excellent educational web page or site about spring design and manufcture and feel it should be included in the list below.