Review on Ableconn PIUSBSDXC Raspberry Pi USB 2.0 to SD 3.0 (SDXC) Converter Stackable Board by Brian Campbell

I am using this serial expansion board to pass the Serial/RS232 signal from the ultrasonic sensor to the TX/RX pins of the Raspberry Pi, which requires TTL instead of RS232. Works like clockwork. I simply placed two jumpers (from the ultrasonic sensor) on pins 2 and 5 of the DB9 connector on this board (see attached image) and connected the supplied jumpers to the Pi. No other changes were required. HIGHLY RECOMMENDED.