Not just a simple breakout board, this microSD adapter goes the extra mile - designed for ease of use.
Onboard 5v->3v regulator provides 150mA for power-hungry cards
3v level shifting means you can use this with ease on either 3v or 5v systems
Uses a proper level shifting chip, not resistors: less problems, and faster read/write access
Use 3 or 4 digital pins to read and write 2Gb+ of storage!
Activity LED lights up when the SD card is being read or written
Four #2 mounting holes
Push-push socket with card slightly over the edge of the PCB so its easy to insert and remove
Comes with 0.1" header (unattached) so you can get it on a breadboard or use wires - your choice
Tested and assembled here at the Adafruit factory
Works great with Arduino, with tons of example code and wiring diagrams
To use with an Arduino, connect GND to ground, 5V to 5V, CLK to pin 13, DO to pin 12, DI to pin 11, and CS to pin 10. Then you can use the Arduino IDE's SD library which supports FAT and FAT32 SD cards.
Dimensions (without 0.1" header):
Length: 31.85mm/1.25in
Width: 25.4mm/1.00in
Height: 3.75mm/0.15in
Weight: 3.43g/0.12oz