Piping Nozzles (Tips): This specific set appears to be a 12-piece kit featuring stainless steel nozzles designed for versatile designs. Common shapes include stars, petals, and rounds for different textures and patterns.
Piping Bag: A reusable pastry bag (often made of silicone or thick plastic) is used to hold and dispense the frosting.
Coupler: While not always visible in every shot, many kits include a plastic screw-on coupler to securely fasten the nozzles to the bag, allowing you to switch tips without emptying the bag.