The SCHMERSAL EX-BN 20 series of screw connected, Ex certified, Magnetic reed switches are enclosed in full aluminum enclosures, ensuring long equipment life. Dimensions are 104 mm x 52 mm x 47 mm. Moreover, they follow a non-contact principle. All units have 1 reed contact, and an actuating distance up to 50 mm banking on the version and the actuating magnet.