Each hide of leather used has been hand-selected from ethically sourced tanneries in the United States, and heavily tested to confidently guarantee life-long use.
The majority of my wallets and goods, unless stated otherwise, are made with Vegetable Tanned Leather, generally from Hermann Oak -- one of the oldest operating tanneries in America. Veg-tanned leather is a chemical-free leather that is given its color through a natural process using organic tannins found in bark and leaves. This tanning process generally takes between 30-90 days.
Vegetable Tanned leather is famous for its remarkable aging process. The material is greatly influenced by its environment and will initially change color like human skin when exposed to direct sunlight. This leather ages to a beautiful dark caramel brown, and will burnish darker in spots of frequent contact. 
thread choice has also been carefully considered for my products. The majority of my items are either stitched with Ritza Tiger thread, polycord thread from Maine Thread Company, or in the case of machine sewn products, SGT KNOTS' #69 & #92 Bonded Nylon Thread.
Other leathers that are seen in my store are:
Hot Stuffed Leather does not describe a specific type of leather, but a process that is done to leather. Hot Stuffing literally means stuffing a hide full of animal waxes and tallows (processed animal fat) until the hide is fully impregnated through the core. Hot stuffing creates an amazing feel, and results in a leather that will basically take care of itself for many years as the oils and waxes from the core are drawn up to the surface
Latigo is a steer hide that is alum tanned and drum dyed. Latigo is most easily explained as the waxed canvas of leather; it is a utilitarian tanage meant for use in all conditions. Because of the tanning process, latigo lends itself nicely to outdoor use due to it's resistance to water.
I also will sometimes work with certain exotic leathers in smaller projects to include snake skin, shark skin, gator, elk/deer, lizard, and fish leather.