Seif Design is an Estonian design studio best known for minimalist card wallets made with natural stone. Founded after beginning as a student company, the brand develops its products around durability, simplicity and natural materials.

Its main collection combines metal card holders with unique stone finishes, alongside lighter card wallets, wooden designs, stone earrings and wood-backed phone cases. Seif Design carries out all production at the Hammerjack production facilities in Estonia, where production runs on green energy.