Dr. Oetker Klop-Fix is a whipped cream stiffener. Klop-Fix ensures that the whipped cream remains nice and firm and prevents the cake base from softening too quickly. With a bag of Klop-Fix the whipped cream looks nicer and firmer. Klop-Fix is easy to use. One bag is sufficient for 250 ml of whipped cream. You add it to the whipped cream while whisking.