The 3SE2120-1D is a Siemens metal limit switch with snap-action contacts (1NO+1NC) and a roller plunger actuator (Type C). It features M20 x 1.5 threading for mounting. However, this product has been discontinued since December 31, 2011, and its successor is the 3SE5112-0CD02.

Type: Position switch, metal-enclosed

Contacts: 1 Normally Open (NO) + 1 Normally Closed (NC)

Actuator: Roller plunger (Type C)

Threading: M20 x 1.5

Protection Class: IP67

Lifecycle: Discontinued since December 31, 2011 (Successor: 3SE5112-0CD02)