Materials and Care

Sustainable tanning

All the leathers we use are vegetable-tanned with high quality environmentally safe processes, making them some of the finest in the world. The tanneries that KASPERI works with have decades of experience in traditional leather making. The tanning process takes several weeks and involves more than 50 separate stages where special expertise and handcraft skills are called for. The tanneries have very high standards for sustainability, environmental protection and social responsibility both in raw material acquisition and manufacturing.

Leather chosen for longevity

Leather is our material of choice and we choose to use thicker leather instead of having linings. Thicker leather without linings makes bags last longer and repairs more accessible and durable.   

Our main material is 2mm and 3mm full grain vegetable-tanned European bovine leather. The full-grain bovine leather is made from the best top part of the hide. It is sturdy, weather resistant and ages beautifully. The leather we use is less processed and minimal coating has been applied so that the unique features of each hide can be seen. Small marks, scars and imperfections of each hide make each KASPERI bag unique.

We also use excellent 2mm yak leather sourced from Mongolia and tanned in Finland. The yak has a natural pattern on the surface and is sturdy yet supple so it works great in our Fold Top backpacks. We also use the supremely supple and tenacious 1.8mm-2mm Finnish wild whitetail deer leather, also vegetable-tanned in Finland. The whitetail deer is a non-native species in Finland and its population growth is managed by hunting clubs, and that is where our leather is sourced from.

Leather care

To keep your backpack or bag in the best shape, treat it every 2-6 months or when the leather feels dry, with leather wax. Brush and wipe the leather to clean it. With a cloth spread a pinch of wax on the leather. Avoid too much wax or saturating the bag with wax. Allow the wax to permeate overnight and then polish remainders off with a cotton or wool cloth. 

We recommend using our own leather wax made of beeswax and genuine Finnish wood tar, or just beeswax. Do not use synthetic chemicals or leather sprays.

A KASPERI bag provides good protection against weather. It doesn't let the water easily through. When it gets wet, just let it dry in normal room temperature and it is good to go. To further weatherproof your KASPERI and keep it in the best shape, treat it from time to time with wax or oil.

Metal hardware and care

The KASPERI designed buckles are laser cut and made of high grade AISI 316 stainless steel for durability that will probably outlast humanity and is infinitely recyclable. The stainless steel buckles and other hardware are maintenance­ free.

The steel rivets come from Italy and are coated for slow corrosion down. When you wax your bag or backpack, be sure to cover the rivets with the wax as well, as it protects the steel. The rivets are quickly replaceable and used for reinforcement in high stress points as well as in places where replacement of parts can become relevant.

The roller buckles come from Sweden made from chromed steel for protection and are maintenance free.

The Tanneries

Bovine hides from SOHRE Leder, Germany

Currently SOHRE is our main supplier of Bovine hides in most of our products. The bovine hides are sourced from France and tanned using a pure vegetable-tanning process in Germany, free of environmental toxins like all of the leathers that we use. Their leather is extremely sturdy and tough, perfect for products that are intended to last for life. 

SOHRE Leder is a tannery with an impressively long experience, using pure vegetable tannins, without any surface treatment, only dyed and waxed, specially greased, according to a 120 years old recipe of the tannery Krekelberg in Germany.

Bovine hides from Tärnsjö Garveri, Sweden

The art of vegetable tanning leather is thousands of years old. Since 1873 Tärnsjö Garveri has been using these time-tested methods. Industrialization has allowed tanneries to offer standard hides at lower prices and many tanneries have chosen that path. Tärnsjö chose quality over quantity. Tärnsjö sources its bovine hides from Sweden and Finland. 

The aesthetic of vegetable tanned leather is unparalleled and the patina that it develops with use over time cannot be produced any other way. It is also the only way to produce premium leather of desired quality while at the same time respecting our environment.

Yak hides from Kokkolan, Finland

The Yak hides have exceptional tensile strength and are considered abrasive resistant. As yak leather is difficult to source, Kokkolan is the only tannery in Finland that tans yak leather. The hide has evolved to what is called ”A shelter for all seasons” with thin, light, compact, woven collagen fibres and a fine closed grain, a leather for the toughest of conditions. 

Yaks are among the largest bovids in shoulder height and it’s physiology is adapted to high altitudes, exceeding 3000 meters. It has adjusted to the climate for over thousands of years which has given its hide some very unique characteristics.

Whitetail deer hides from Ahlskog Tannery, Finland

Ahlskog Tannery is specialized in the highest quality deer, reindeer and elk leather. Their whitetail deer leather is sourced from Finnish hunting clubs and would otherwise go to waste. They've developed a custom tanning recipe for the Kasperi Specials S.03 Whitetail Fold Top.

The whitetail deer leather has an extremely supple yet tenacious quality to it making it a perfect material for more flexible products such as the Fold Top. It is also a tad lighter than the Mongolian yak leather.