wireless mailbox alert system

Wireless mailbox alert recommendation
Many ways for system to fail
Check mail the old fashioned way
Paul Loudenslager, who needs to read up on Job and lives in Tifton, Georgia wrote to me.
«I don’t know how far your house is from your mailbox, but my mailbox is approximately 350 feet from the house. It’s tiring at my age to travel back and forth several times a day to see if the mail has arrived. My mail is delivered at various times.
Can you recommend a reliable wireless mailbox alert system alert that will transmit at least 500 feet?
There are pine tree branches hanging down possibly in the line of transmission, but they can be cut.
Mail Alert System — Description
Designed to notify you of the arrival of mail, the STI Wireless Mailbox Alert with Chime is built to last! Triggered by the opening of your mailbox door, the sensor and receiver communicate using a wireless radio signal. With a range of up to 1000’, the chime will sound and flash after the signal is received, letting you know the mail has arrived! This unit also has a built in protection feature, if the transmitter is removed, stolen, loses signal or has a low battery, the receiver will generate a consistent beep every minute until acknowledged!

The sensor, operating on one (1) 3V lithium battery, should run for up to 5 years without replacement when used normally, and the receiver operates with a 120 VAC input/12 VDC output adapter (both are included).
Product Features

Mailbox sensor alarm with 1000 series receiver
Every time the mailbox alarm is opened, sensor will send a signal to the receiver to chime
Sends signal to receiver up to 1,000 feet away when mail arrives
Adjustable swivel sensor allows easy mount on any top- or bottom-hinged mailbox door
Choose among 16 different alarm chimes
The receiver supports up to 4 sensors for setting up at different zones
Each zone can be set with a separate alarm tune to distinguish one from the other
Indicator lights show which zone is activated
Alarm apparatus for indicating when mail has been delivered to a mailbox www.mailboxsensor.com A photocell inside the mailbox has an electrical characteristic dependent upon the presence of light in the mailbox, and this electrical characteristic is coupled to an alarm signal device inside a house. The alarm signal device latches on after mail has been delivered and light has entered the mailbox changing the electrical characteristic of the photocell.