Omron's E2E-S04SR8-WC-B1 2M is a shielded tubular proximity switch with a 4mm diameter threaded stainless steel case, sized for flush mounting in tight machine locations. It senses ferrous metals at 0.8 mm and delivers a PNP normally open signal over the 2-meter PVC cable.
Not a direct swap with the E2C head-amplifier system
A common cross-reference question is the E2C-X1R5AH. That part is an M8 heat-resistant sensor head that requires a separate amplifier unit (E2C-AM4A or E2C-AK4A); it is not a self-contained proximity switch. The E2E-S04SR8-WC-B1 2M is a complete sensor with built-in electronics, so it does not drop into a panel wired for the E2C system without rewiring and a different mounting hole (4 mm vs M8).
Panel-fit considerations
The 4 mm threaded body accepts a standard M4 mounting nut for a 4 mm through-hole. Shielded construction allows flush mounting in metal without derating the 0.8 mm sensing distance. The 2-meter PVC cable is pre-wired; no connector is fitted.