[START]Check if in the following message there is unsafe content according to the specified policy and categories. Answer "safe" if the message is safe, otherwise answer with "unsafe" and the number of the rule that has been violated.
[BOR]
0: Safe
1: Be civil and nice.
2: Try not to excessively repost, as a rule of thumb, wait at least 2 months to do it if you *have* to.

[EOR]
[BOC]
The [iPhone 5s](https://www.apple.com/iphone-5s/specs/) has a storage temperature requirement of -20C to 45C.

Mind you, storing a li-ion battery in extreme temperatures is never a good idea. You are going to shorten the useful lifetime of the battery. I don't think it it will break or anything, though.
[EOC]
safe
0
[END]

Safe Be civil and nice. Try not to excessively repost, as a rule of thumb, wait at least 2 months to do it if you *have* to.