Review on 📚 HiLetgo 5pcs Micro SD TF Card Adapter Reader Module with 6Pin SPI Interface for Arduino UNO R3 MEGA 2560 Due by Lamar Vanderburg

Do not purchase for Teensy 3.2. Got this to help me upload sound files to the prop board for my Teensy 3.2. The Teensy boards have 3.3V logic while the Arduino has 5V. I couldn't get the example sketches to recognize the Teensy 3.2 SD card reader, but I was able to connect it to my Arduino Mega. SD cards work at 3.3V, so there is a voltage regulator to prevent the 5V signals from Arduino from destroying the SD card. My guess is that the voltage regulator for the SD card reader is limiting the tiny 3.2 signals so it doesn't register at 3.3V for the SD card. Note: I tried connecting Vcc to Vusb with 5V but it still doesn't work. This doesn't change the fact that the MOSI, MISO, SCK, and CS pins operate at 3.3V. If you need it for a 3.3V microcontroller, don't buy it. If you're using a 5V microcontroller like most Arduinos, this will work fine. I'm only giving this 3 stars because the description sounds like it will work for 3.3 volt logic.