Maybe some 433mhz PIRs might have the range for some?
These ones are playing well with a sonoff rf bridge flashed with Esphome.
Haven’t tested distance (no need for me). Ad claims 80m.
#Aliexpress AU $10.77 11%OFF | 433Mhz Wireless PIR Infrared Motion Sensor Alarm Detector With Flash Led Light for Smart Home Security Alarm System
Yes 433MHz might work, but I am not sure how a pir would detect whether someone has put a letter in my mailbox.
I see palm trees in the photo’s background. Where I live, winter temperatures can drop below -20 C so that makes battery-operated sensors a tricky choice.
Our mailbox is attached to our home’s brick facade. It took me a day to fish a wire from the basement up through the narrow air-space between the exterior sheathing and brick wall (in fact, the wire runs though flexible conduit that I forced into that space from the basement). The hardest part was fishing it through the hole I drilled in the mortar to emerge behind the mailbox (think about it and you’ll appreciate the magnitude of the challenge).
All’s well that ends well because now a contact sensor can detect the opening/closing of the mailbox’s lid without concern for temperature, battery-life, or RF signal-strength.
Isn’t the sensor in the OP a PIR?
Edit: Oh I guess you mean will the PIR detect a letter through the slot?
Yes, mail through the slot is my aim.
Maybe just PIR sensor fixed at the top or bottom near slot pointing straight up or down might work? Depending on mailbox layout…
A pir sensor is not going to detect mail as far as I know.
In the video in post 1, I am guessing the pir detects the postman,who has to open the door to put the mail in.
About 8 meters, mostly free sight.
same here, anyway ordered from ali , need to wait a month now 
Hi why 2?
Metal and magnet? Strange… how you put the magnet?
Theyre just put on as usual. I have one for mail and one for emptying.
Yeah…I live in Florida but I wish I could directly power my contact sensor. Unfortunately my mailbox is a at 40 feet from the closest power source (and would have to run under pavers and the concrete sidewalk). I would have loved to use a wemosD1 instead. I thought I had this working with a Fibaro zwave Motion sensor and then an Iris zigbee motion sensor, but both would stop reporting shortly after install…my mailbox’s housing is thicker than the average metal box so I had to go external. Luckily I had all the parts needed sitting on my workbench and got it setup in 30 minutes. Very happy with this setup.
Love the toilet roll holder! I just ran out this morning 
Can you please further explain “one for emptying”. I am guessing you mean one for when the mail is delivered and one for when you retrieve said delivered mail but how does that work?
You can buy plastic ones 
but that’s very un-eco-friendly 
Edit: I know your issue was battery life but you did seem just a tad jealous too ! (I knoiw I am)
I have two hatches, one for delivering the mail and one for emptying the mailbox
I don’t know if this would be considered exactly as “innovative “ but wanted to share nonetheless:
I am so sick and tired of Netflix (et al) who purposely stops the programming after a certain time (the intrusive “Are you still watching?”)
Ugh. I hate that, so I created a simple automation for my media player (Apple tv) to resume play to get rid of that passive aggressive screen. When I checked the states tool, it noted that it was “paused,” so I automated accordingly. Additionally I use a time condition so that it does it during the day, and so forth.
Take that Netflix!
So now you can never stop watching? 
It is not so much about watching as it is listening. Complete silence makes me nervous (a personal, quirky attribute) so when I’m in the other room I prefer to have the comfort of constant sound. But alas, the above didn’t work (so don’t try this at home). The video still played in the background, but it wasn’t enough to stop that horrible popup.
I mean, Netflix is being outright jerks at this point. You can actually see the video playing, albeit blurred, yet the popup still comes on the screen, “Are you still watching?”
edited to add: However, it makes for a fantastic transition. While Netflix loads the next episode, music starts playing, then stops when the episode begins.