Contactless Card Payment Systems from Merchant Warehouse: OTI Saturn 5000 (Contactless Reader) New. The OTI Saturn 5000 tap and pay terminal could be your best choice if quick transactions are important to you. Contactless payment processing is becoming more and more popular, and the OTI Saturn 5000 is one of the most trusted readers. The OTI Saturn 5000 contactless reader relies on a secure internal memory and a small antenna embedded in a device that communicates with a reader through a contactless radio frequency interface. The OTI Saturn 5000 is designed to allow for consumer to "tap and pay," eliminating the wait for credit card authorizations and signature collection.