My Cart


Duca del Cosma only processes high-quality calfskin and cowhide leather. Our animals come from Italy, and due to their pore size, we only select hides from smaller animals. When it comes to skin, it‘s a simple choice. Skins have two sides: the outside, which is usually covered with hair, is the more robust grain side, the inner side is the flesh side. For the exterior of our shoes, we only use the more resistant grain side. Most cowhide leather available on the German market is chromium tanned (mineral tanning, in baths). In addition to this, leather intended for Duca del Cosma is submitted to a hydrophobic treatment directly after tanning: the leather is made water-repellent using a chemical procedure, without altering its natural characteristics.


A membrane is like a wall separating liquids and gas. Liquids can‘t enter but gas in the form of water vapour (sweat) may escape. Membranes ensure that shoes and clothes are breathable, and this is of utmost importance to Duca del Cosma.

Membranes for shoes

For the interior finishing of Duca del Cosma shoes we use a micro-fibre material with a membrane and waterproof tape sealing. Duca del Cosma employs the Cosmo-hbr membrane, one of the best on the market. We spend a lot of time and money on testing waterproofness and functionality to ensure your feet remain constantly dry, whilst still being able to “breathe”. Even so, the upper leather has to be treated in regular intervals to ensure humidity runs off and does not soak in, so that the leather maintains its suppleness. We guaranty waterproof under normal wearing circumstances and up to 4,5 cm on the boot from the ground.