I didn't receive it, the store refunded it.
The 1602 display is only a 4-wire connection if you use the II2 adapter, but it was even easier than 4-wiring because all you need to do with this hat is to put it on top.And I must confess that I don't use keys in my project, because I don't use them.But I think it's good that you can complete it by just putting it on top.