Solar weather proof doorbell for back gate

How about a Solar or battery operated weather proof doorbell for the back gate?

Same. I own a farm. No one can get to my house (where a doorbell would be) without trespassing and being eaten by a dog or two, so I need a doorbell for the front gate. Solar/battery would be ideal.

I’m sure I’m not the only one who doesn’t have an existing chime. A battery doorbell or solar powered doorbell would be great.