Help on adding simple powered sub

I am debating on 2 ways to get rca outputs to run powered sub. I am looking at the following 2. On one hand I would have to tab into factory radio. The second has patch inline and provides remote power. This is for a 2021 off road with non-amp radio. Has anybody used the inline patch?

 

I use the kicker one it works great . Just splice it into one of your speakers and your good .

 

This is what I was going to recommend. OP, what powered sub were you going to go with?

The kicker hideaway doesn’t need RCA. It can use straight speaker wires. The alpine might as well, but I don’t know for sure. The kicker 8” also fits under the drivers seat.