Geekstory 5 PCS Micro SD Card Module Mini TF Card Adapter with Memory Storage Breakout Board SPI Interface Driver + 40 PCS Female to Male Dupont Cable Line for Arduino Raspberry Pi

I connected to Mega 2650 and defined my CS pin, works fine. MISO, MOSI and CK pins go to the hardware pins 50,51,52.

worked as expected

Got these because I needed one for an Atmel based Retro IC Tester (you can find it by Google). It works fine, but because the mounting is vertical, the spring loaded micro SD card slot would be better as one of the simpler friction fit slots. Now all I have to do is figure out what I am going to do with the other 4 adapters and those nice patch cables. ;)

Works perfectly with Arduino Uno. Be sure to select CS, chip select = pin 4.Built-in sd demo in the Arduino IDE. SCK pin 13, MOSI pin 11, MISO pin 12Vcc to 5v and gnd to gnd

The nano boards work ok, after you reflash a new bootloader to them. I kept having arduino ide give me errors when uploading a sketch no matter what board or bootloader version I tried (old and new). Reflashed the bootloader and no more issues.

Worked well right away. Easy to hook up and program with standard Arduino SD library.