4 pcs of used Omron E2E-X1B1 Miniature Proximity Sensors for sale.  Powered from 12 to 24 V DC, output PNP open collector, normally open. Senses magnetic metal at 1 mm.  Cables at least 100 mm long.

Delivery by Priority Letter, no tracking. Tracking can be purchased separately. Priced at a fraction of new list price. Auction price is for 4 pcs.