How To Make This Shot?

I need help figuring out what is in this shot? The bartender called it a grapefruit kamikaze. I know it has grapefruit vodka in it, and I know you shake it w/ice to chill. There are 2-3 more ingredients, but not sure what. When you drink it, you get a refreshing grapefruit taste, but it's not sour like a kamikaze. Any help would be greatly appreciated.

Maybe instead of using the Lime Juice he used grapefruit juice instead.  Or a mix of both so it's not so sour...  Ingredients just like the site says - Vodka, Triple Sec, Lime Juice or if you go with number 3 instead of lime juice, sweet and sour.  You'll just have to test them all...  Happy drinking!