4x4 Keypad 16 Key 4PCS Matrix Array Membrane Switch Keypad Keyboard for Microcontroller

Based upon some of the other reviews, I decided to test all 4 keypads right away. Since the keypads did not provide ANY documentation, I went online and found the standard connections for a keypad. The new keypads exactly matched the standard connections and all of the keys on all of the keypads worked flawlessly. I agree with one of the other reviewers that a wiring diagram would have been nice.

Seem to be good quality, but I’m have yet to actually get them to work… maybe someday

I did not expect the contact resistance to be so high ~50 ohms. That said, the application I was investigating should not care. The connectors are a little flakey so I would advise seeing how uniform the contact resistance is across the switches.

well made key pads. Just wish they would include a schematic somewhere. I had to find a diagram on the internet which ended up being opposite of the keypads I bought. Was easy to change the pins. I'd definitely buy again.

It helped me to prove of concept of a project. Not difficult to program.

This product is exactly what I needed!

I wanted to try building an escape room in a box for fun so I needed a few of these. Luckily 3 of the 4 work so I'll have enough, but I wish I had only paid 3/4 of the money. Documentation would have been nice as they do seem to be opposite of what I had found on other sites.

Used a meter to check every key. First row of the first keypad I checked had 2 dead keys. Turns out every keypad had multiple bad keys. Buy somewhere else.