The Sennheiser MMD 935B is a cardioid capsule. It can be used to capture audio when paired with a receiver and the SKM 100/300/500 G3/G4, SKM 2000/6000/9000, SKM D1/AVX, or SL handheld DW wireless handheld transmitters (sold separately). The capsule is easily installed, includes a metal grille, and replaces faulty or damaged capsules. The interchangeable capsule system allows users to select among capsules with differing sensitivity levels and polarity patterns.