Cocktail Flex Kits Liven up the summer fun! Use these fun cocktails to liven up parties or decorate for ’happy hour’. We are out of the margarita with lime, tropical umbrella and Martini with olives. Flex Packs are sold individually, please choose from the choices in the drop menu. Each package comes with everything you see here and measures 5. 5 x 5 x 0. 1.