WMF Perfect Premium Replacement Part Double Seal for pressure cookers with residual pressure safety, 2.5-8.5 liters, Ø 18 cm and 22 cm. The safety valve is compatible with all pressure cooker models featuring residual pressure safety from the Perfect Premium series with Ø 18 cm (2.5 l) and Ø 22 cm (3.0 l, 4.5 l, 6.5 l, and 8.5 l). The success story of WMF Perfect pressure cookers continues. The Perfect Premium now brings new energy to the kitchen by making fast, healthy cooking even more comfortable and easier. This is thanks to the proven all-in-one rotary knob that can be operated with one hand. This advancement of the Perfect series impresses with its consistently perfect functionality and highlights WMF's leadership in energy-saving pressure cooking.