The LSTE21 is a limit switch operating head designed for rectilinear motion detection. It features a stainless steel lateral plain plunger for actuation from the end and is compatible with 40 mm or 60 mm width metal casings. This operating head is designed for a maximum actuation speed of 0.5 m/s and conforms to the F Shape standard. As a component of a complete limit switch assembly, it is used in industrial applications for detecting presence, positioning, and travel limits in automated systems.