1Pour 1/4 cup of the limeade concentrate into small bowl. Place salt on small plate. Dip rims of 5 rocks or margarita glasses into limeade and then into salt; set aside.
2Fill blender with ice; add beer, tequila and remaining 1 1/2 cups limeade concentrate. Cover; blend until smooth. Pour into salt-rimmed glasses. Garnish with lime slice.