The blue Multi SIM Cardholder from Classico Worldwide LLC is a one-piece molded plastic credit card sized storage unit. This item holds 3 SIM cards, 4 microSD cards and a Micro SD to SD card adapter. The holder features seven individual slots constructed in such a way that the cards can only be inserted one way - facing down - to protect the electrical contacts. Each slot has a locking tab that holds the card in place. A hole is provided so you can attach the holder to your keychain.