The Klockner Moeller AT21-3-I is a limit switch used in industrial automation. It features snap-action contacts for reliable switching and has an IP65 rating, making it resistant to dust and water. 

Contact Configuration: Snap-action contacts for reliable switching

Protection Rating: IP65 (dust-tight and water-resistant)

Body Type: Compact design with a single conduit entry

Operating Mechanism: Mechanical actuator with interchangeable heads

Application: Suitable for harsh industrial environments