The Blush Mirage Rainbow Shaker is a 20-ounce stainless steel cocktail shaker with an iridescent rainbow finish, cap, and built-in strainer. It is used for mixing cocktail ingredients with ice before serving. The shaker body contains the liquid and ice during shaking, allowing the ingredients to combine and chill. The cap secures the opening during use, while the integrated strainer separates ice and solid ingredients during pouring. Its compact 2 by 2 by 8.5 inch size suits barware storage and handling.