The MPSN-MS discharge airlock is made of gray/nodular cast iron and is used for the direct product discharging of filters, separators or pneumatic conveying and aspiration systems with a maximum differential pressure of 0.8 bar. The MPSN-MS is preferably used for free- flowing, powdery and fine-grained products. Optionally, the airlock can be tested as an explosion decoupling element for protection.