Hopefully you will love having one...I have two...a lighter weight unribbed on (looks more dressy IMO) and a heavy ribbed one...both are very useful, and great item help make your uniform more flexible temperature wise, and heck, even reduce the amount of ironing you need to do.
Heck...the fact it can also be used off duty when out eating is a great plus.
Have bought a few over the years... GALLS, a police speciality retailer usually has them also, buttons, and some are even water repellent, depending on the style.