Historically, this order (specifically the version from 2017) established the rules for (MTO) for the Russian military. It covers:
The comprehensive manual on how the army is supplied.
Strict requirements for documenting the consumption and loss of property. Understanding the Request
There may be specific local or older variants (e.g., related to military education or health standards) that use the same number.
Which specific or year of Order 555 are you interested in generating a piece about?