Review on 🔌 Qunqi IIC/I2C/TWI 1602 Display Module: 16x2 Serial LCD with Blue Backlight for Arduino UNO R3 MEGA2560 by Chris Cruz

This contrast is no joke! Turn the contrast (the screw next to the input pins) until you see black squares, then go back to where they just disappear. One of the previous reviewers said to adjust the contrast before messing with the code. If only I had listened. I thought it was because the address was 0x3F (which it is). Turns out my contrast was basically turned off. For this they lose a star because it makes no sense to send it in this form. I also had a bent pin in shipping, but it's easy to straighten. In general I'm happy. 4 stars. :)