Named range drop-down

[jgelpi16]

I know this is a simple question/solution because I have done it before. I have a named range and I want to have a field reference that named range. I want it to look like a combo-box (See attached image). I have pulled my hair out trying to replicate this . I know it refers to a named range, but I don't know how it ties to that named range. I am using Excel 2010. Thank you.