The 3SE2924-3AA20 is a mechanical limit switch from Siemens' 3SE2 series, featuring a roller plunger actuator with a 30 mm horizontal roller. It provides 1 NO (normally open) and 1 NC (normally closed) contact, rated for 10 A/250 V AC or 5 A/30 V DC, with a mechanical life of ≥1 million operations.