Material Guide 

While continuously evaluating new materials and techniques for Flattered, we today believe in leather as a natural and strong material that can withstand time over artificial leathers. All leathers we use in our products are bi-product leathers from other industries. By sourcing the best possible leathers — certified by the Leather Working Group (LWG)

— for our shoes, bags, and accessories, we ensure our materials stem from environ- mental best practices and performance in all areas of leather production, including chemical and water management, energy use, greenhouse gas emissions, waste management and hide traceability.

When it’s possible, we aim to use leather that is chrome free. Still, we value a suitable certificate from LWG more than focusing only on chrome since a good certification means that the tannery has good overall waste and water management, not only for chrome. Nevertheless, 50% of our leather is chrome free since we only use chrome-free leather as our lining.

For 2024, 100% of all our leathers come from partners that are either audited or members of LWG, and 65% of those leathers are from partners that are either silver or gold-rated by the same organisation. We are working to increase this percentage seasonally.


Our leather comes from the tanned rawhides of animals – most commonly cows, goats, or sheep – and is a by-product of the meat industry. We have committed to never using exotic skins due to their unacceptable risks regarding animal welfare. All products with a reptile effect use cow leather embossed and printed to look similar to exotic skins. Leather is sensitive to damage – the softer the leather, the easier it may scratch. The tanning process is, therefore, essential – it preserves and strengthens the rawhide and makes it supple and more pliable to work with. Below we try to explain the differences in tanning processes that affect both you, those working with the leather, and our environment.

Suede is made when the leather is split, removing the outer grain and leaving behind a soft inner surface with long fibres and a smooth, velvety feel. However, since the inside of the hide is not as durable as the outer grain, suede is more susceptible to scratches and staining.

Leather Outsoles

Some of our shoes have leather outsoles. Leather-soled shoes look great and allow the foot to breathe, as they are a natural membrane. The leather has low wear resistance, so the leather sole may be deformed when worn in wet weather. Therefore, we highly recommend you visit the cobbler and put a protective rubber sole on top before first use to avoid tearing the sole and to get a better grip.

Chrome tanned  Leather

Chrome-tanned leather is the most popular way of tanning leather. It is a quick method and can achieve a finished product in days. The hides have been in acid, salt, chromium sulfate, and other chemicals. The leather is neither biodegradable nor environmentally friendly (the process results in toxic wastewater that negatively impacts the environment). However, from a product life cycle perspective, it is the most long-lasting. In addition, chrome-tanned leather is more resistant to water, heat, and stains.

Chrome free Leather

Chrome-free leather is leather that has been manufactured without using chromium in the tanning process. Doing so means less pollution, cleaner waste streams, and improved biodegradability. The characteristics are similar to chrome-tanned leather but have a lighter environmental footprint. However, leathers made with this tanning agent require more chemicals to improve the material's properties after tanning. For this reason, the effluent of the chrome-free process requires additional treatment before it can be used in production.

Vegan Materials

Vegan substitutes for leather can be made from pineapple leaves, mycelium, cork, apple peels, or other fruit waste, as well as recycled plastic. This material is often much thinner than the genuine leather and far more lightweight. It is, therefore, less durable than leather and should be treated with extra care.

It's important to note that most materials classified as "non-leather" aren't necessarily eco-friendly. For example, the most commonly used materials to create faux leather include polyvinyl chloride (PVC) and polyurethane (PU), plastic-based materials made from fossil fuels. At Flattered, we continuously work towards entirely removing these types of materials from our offering.

Recycled Cotton

Recycled cotton enables waste to be reused more effectively. For example, cotton can be recycled from post-consumer garments or pre-consumer industrial waste, such as yarn or excess fabric, generated in garment production. 

Cotton waste is sorted by color, shredded, and blended into new fibers. The cotton fibers become shorter and weaker after recycling, so recycled cotton is often combined with a non-recycled fiber for strength. Because recycled cotton is not dyed, the energy and water used in production are typically lower than regular cotton.

Recycled Polyester

Recycled polyester production generates fewer CO2 emissions than virgin polyester and doesn't require new petroleum as a raw material. Instead, the process takes something previously treated as waste – from pre-consumer sources such as fiber waste during the production of virgin polyester or post-consumer sources like PET bottles – and gives it a new life. Polyester material comprises at least 50% recycled polyester fibers and is certified by the Global Recycled Standard (GRS). GRS aims to reduce production's harmful impact and ensure that materials used in the final product have been recycled and processed sustainably.

Recycled Nylon

Recycled nylon has the same benefits as recycled polyester: It diverts waste from landfills, and its production requires fewer resources than virgin nylon, which utilizes significant amounts of water, energy, and fossil fuel. 

The material comes from sources such as old carpets, leggings, or old fishing nets. Using these sources is an excellent solution for preventing garbage from landing in the ocean.

Recycled EVA

EVA (ethylene-vinyl acetate) foam or resin is a light and flexible material used for padding in shoe production. EVA foam is considered eco-friendly because it is BPA (Bisphenol A) free and does not contain chlorides, heavy metals, phenols, latex, or other toxic substances. In addition, EVA foam products are soft, flexible, and resistant to chemical corrosion.


Cork is a natural material that has been used for over 5000 years. The material is obtained from the bark of a tree – the Cork Oak (Quercus suber L.) – a slow-growing, evergreen oak that flourishes only in specific regions of the Western Mediterranean (Portugal, Spain, southern France, parts of Italy, North Africa) and China. Cork is considered to be a renewable or sustainable material because harvesting it doesn't require the cutting down of any trees.

  • Natural Rubber

    At Flattered, we offer boots with soles made from natural rubber. Natural rubber is created from the milk of the Hevea tree. Therefore, it is a renewable resource and helps the tree to flourish. Natural rubber is also easy to recycle and biodegradable.

  • Wool

    Wool is a standard natural fibre that is obtained mainly from sheep. It is renewable, recyclable, and biodegradable if not treated with chemicals. Wool is best known for its warming properties when it's cold but is also temperature-regulating, helping stay cool when it's warm. The structure of wool fibres enables them to trap air and absorb moisture without becoming damp.

  • Thunit

    Many of our shoes are fitted with a thunit outsole. Thunit is a type of resin rubber that lasts longer than regular soles made out of leather – so there's no need to replace or add an extra sole to reinforce your shoes after purchase.

  • Metal

    Many of our products are made with metal details. The metal we use is called Zamak. Zamak is part of the family of metal alloys, with a base metal of zinc and alloying elements of aluminium, magnesium, and copper. It is free from nickel and finished in an eco bath. 

    The Zamak die-casting process disperses negligible emission levels into the air and water. Furthermore, production waste is recyclable, and the energy consumption is deficient.

  • Leather Outsoles

    Some of our shoes have leather outsoles. Leather-soled shoes look great and allow the foot to breathe, as they are a natural membrane. The leather has low wear resistance, so the leather sole may be deformed when worn in wet weather. Therefore, we highly recommend you visit the cobbler and put a protective rubber sole on top before first use to avoid tearing the sole and to get a better grip.