What the double-distance rating means on your line
The E2A-M18KS08-WP-D1 2M is an Omron Standard Double Distance Sensing proximity switch in an M18 barrel. The 'double distance' means it detects a target at roughly twice the range of a standard M18 inductive sensor of the same diameter — so you can mount it further from the target or sense a smaller target at the same standoff.
Sourcing and lifecycle — active, no replacement drama
Lifecycle status is current, meaning Omron still builds this order code and you can specify it into a BOM without worrying about an imminent phase-out. No official successor has been announced, so the E2A-M18KS08-WP-D1 2M is the part you want — not a cross-reference to a newer variant. Quoted to order against your quantity; availability confirmed at quote time.