It is clear that if your Magic Mouse is the model that recharges through a lightning port, this article is not for you, but if you have a Magic Mouse 1 of those that have two AA batteries inside it may be that stopping to read this article at some point will get you out of a hurry.
I decided to talk about this because a few months ago I had to look for the replacement of the cover of a Magic Mouse 1 because the son of a co-worker when trying to change the batteries of the same, when he tried to close the aluminum cover of the mouse he broke the tab that made it fit.
There are currently two Magic Mouse in the street, the current Magic Mouse 2 model that has internal batteries and is recharged like the Magic Keyboard through a lightning port like the one Apple has implemented in other devices, and the Magic Mouse 1 that It has a lower aluminum cover that must be removed to be able to change the batteries.
If for whatever reason you have spoiled that small aluminum lid you can get a pack of two units of it in the sales portal for online aliexpress. The pack has a price of 9,11 euros, a price that looks very tight considering that otherwise you would have to buy a new Magic Mouse 2 whose price is much higher or go through the official Apple technical service.
Without a doubt, there are times when these Internet sales portals save us from having to spend large amounts of money on things that do not need it.