3-yarn LSF (Low Shrinkage Fleece)

Thanks to the LSF treatment, our sweatshirts do not lose their shape. You often hear about LSF treatments, but what does this really mean and what is the process?

Cotton is a material that can shrink easily if it is not pre-treated. This is why the fabric used to produce our sweatshirts is pre-shrunk.

No one likes it when their favourite sweatshirt shrinks in the wash, and we’ve all been through this disappointment at least once. Never again! Thanks to the LSF pre-shrinking treatment undergone by the fabric before assembly, the chances of the consumer seeing unsightly shrinkage in their garment after several washes/dries are reduced.

A blend of materials is combined with this fabric treatment: by adding recycled polyester to organic cotton, the composition of our sweatshirts allows us to achieve a perfect balance of materials. This blend contributes to the stability of the fabric.

Firstly, the designation LSF, Low Shrinkage Fleece, refers to a technique in which the fabric is pre-shrunk. The fabric undergoes this treatment in the factory, where it passes through various machinery and techniques to be pre-shrunk.

The 3-yarn designation is also added to the term LSF.

These 3-yarns refer to the 3 layers of fabric:

  • The first is the garment’s outer layer. 100% combed cotton, it gives the product its smooth high-and quality appearance. The combed cotton fibres have been lengthened in an additional mechanical combing process, making the fabric even softer and purer and guaranteeing consistent quality. The quality of this surface is key to obtaining good product printing.
  • The middle layer is made of a continuous 100% polyester filament thread so it is hard-wearing and resistant in the wash.
  • Last but not least, the inner layer is made of cotton and polyester, so it feels soft and comfy to wear.

Are you tempted to learn more about textile pre-shrinking techniques? We’re going to explain all the details about LSF treatments.

Fabrics are treated before the garment is assembled. Meet the two best friends of your Native Spirit LSF sweatshirts: the compactor and the stenter. Nasty names, right? But so practical!

The compactor: wet treatment of the fabric (dyeing and extraction)

The compactor is a compacting machine used to reduce the shrinkage rate of cotton fabrics (jersey, pole, fleece, woven, etc.). It consists of a steam chamber, a felt shrinking calender and a rolling device.

The machine is programmed for one purpose: to recover the compacted fabric without straining it. It works as follows: steam is injected and passed through “chambers” to stabilise the shrinkage as much as possible.

This step allows the fabric to shrink properly without subjecting it to additional tension. Result: an even and consistent dimensional stability is obtained and a finish that is very soft to the touch.

The stenter: heat treatment and drying of the fabric

The stenter is a huge machine similar to a specialist oven that is used in the textile industry to dry- and heat-treat fabrics after wet treatment by the compactor. The stenter consists of various heated chambers adjustable to the width of the fabric, in which temperatures can vary.

Its role is to stabilise the material and obtain regularity in the fabric width. It also contributes to reducing the shrinkage.

The compactor and the stenter both play an essential role in the finishing of the fabric that will subsequently be used to make LSF clothing.


  1. The combed cotton outer offers perfect print quality
  2. The fabric is perfectly stable and resists pilling
  3. Your Native Spirit Sweatshirt is super soft and comfortable, and doesn’t scratch.

    You’ve been dreaming of a sweatshirt that’s both high-quality and eco-friendly. Native Spirit has designed it for you. After all that reading, it’s time for some shopping! Discover our range of LSF sweatshirts and joggers.