I would really, REALLY strongly recommend you not put that 1* on your uniform, police car, or any of your official at-work entry equipment. Don't buy it at all.
I'm not a cop, I'm a soldier but I have completed several fed LE courses. One local cop wore the patch on a hat. The instructors pointed out "Whose ass -- yours or a hostage's?"
Big sticking point on a civil suit if someone is accidently shot or injured while serving a warrant on a wrong address (heck, saw it on "Cops"), or if you acctually DO wound a hostage, and the suing attorney asks why you have that sticker on your take-home cruiser.
Hope you have lotsa money and a good lawyer.
I may be full of it -- like I said, I ain't a cop or lawyer.