This is the low profile Raspberry Pi microSD card adapter and with this you can easily use microSD card for Raspberry Pi. This adapter is near flush with the PCB of the Raspberry Pi once inserted and only extends out about 3mm past the dev board with the microSD inserted.This adapter is only about 3.6mm thick and can easily fit into most cases that could surround a Raspberry Pi without need of removing the case.
microSD card adapter for Raspberry Pi and so on
Raspberry Pi microSD Card Adapter-Low Profile x1
Raspberry Pi microSD Card Adapter - Low Profile(Discontinued)