The space occupied by 10 Lines of standard text is the 'official maximum size and weight' of signature lines at USMB.
Don't shoot the messenger, this is straight from Scooters Rules, and NOBODY fucks with Scooters Rules.
Scooters Rules said:
General:
All messages express the views of the author, not necessarily the views of the forum owners. The owners and moderators of USmessageboard.com reserve the right to remove, edit, move or close any thread for any reason. This is a manual process, however, so please realize that we may not be able to remove or edit particular messages immediately. This policy goes for member profile information as well.
Member signatures may not be longer than ten (10) lines.
http://www.usmessageboard.com/announcements-and-feedback/47455-usmb-rules-and-regulations.html
Did you know that Moderators can edit signatures that are outside of compliance with Scooters Rules?
Note: Size your photos & gifs to a maximum size that's equivalent to 10 lines of standard text.