Instruction: Given a question and its related document, determine if the question is answerable by analyzing the information in the document. Output yes if the document addresses the question, or no otherwise.

Input:
Question: I purchased one of these early in February and only started using it a couple of weeks ago.  Each time the mailbox door is opened, the unit pops open,
Document: Just what I wanted and it works exactly as described, but I had to modify it.I hooked it up the first time and went outside to open and close the mailbox to see if the receiver worked. When I opened the mailbox I could hear the chime at the back of my house, through the closed door, 30 feet from the front of the house. When the chime went off my wife almost wet her pants. WAY too loud, but good if you are deaf.
Not a bad little unit, feels, looks cheap tho'. Works (most of the time). Easy to install, had no problems with that. Replaced with a different style alert unit after using this one for about a month.
Have been using for 2 months. Has never failed so far. The beeping sound inside the house when the mailbox door is opened is loud enough and not too loud as others have stated. I have a front and back door on a thick plastic mailbox with a magnet closure.The alert box is about 75 feet away from mailbox, the signal goes through an inside wall, with glass storm door and heavy solid wood door. The double stick velcro tape is holding up as designed.
This works much better than another I had purchased that only lasted a year and ate batteries. Also this operates every time box is opened before resetting alarm which I really like.
I first placed the base unit in the kitchen at the back of the house, and it worked some of the time. I moved it to a table in the living room in the front of the house, and it has worked perfectly since then. The beeper goes off only when the mailbox is opened, and then the light flashes until it is reset. Now we know when our mail arrives!
So far it is working great. it saves me a lot of time going to check my mail box!!!! My mail man comes at different time every day which was a pian, I should have got it a couple of years ago
I recommend that the sound be dialed down to be about half as loud. My wife finds the notification sound annoying and too loud. It doesn't bother me. I like the fact that when the mail is reliever, you get both a flashing light and a sound from the indoor unit. My unit works great. I wish I had bought one years ago. I used to be frustrated, especially when it was raining, getting the mail because I would make wasted trips to the mailbox.
Easy to install. Has worked consistently through tempatures down to around zero. Mailbox is about one hundred feet from house. Signals every time the box is opened. Has it for about two months with no  problems.
The installation was easy with the double-stick Velcro. I had planned to use the enclosed screw, but doesn't seem to be needed.So far it has worked perfectly at a distance of about 100 feet. I had another type previously that only worked if the door was almost completely opened; this one seems to work even if the door is partially opened.Others have commented on the loud sound. We didn't think it was particularly loud, but not a pleasant sound.
The unit has been working as advertised, but I did attach the velcro strip to mailbox door with 2 tiny nuts and bolts. I don't trust the adhesive alone.
Answer: yes