OxygenOS

This is the Tmobile USA A6013 Unlocked Model and is Single SIM.
Compatible with Verizon, Tmobile, AT&T and all GSM Networks. Will not work with Sprint. Please verify with your network to ensure full compatibility.
Operating System: OxygenOS based on Android 9 (Pie), CPU: Qualcomm Snapdragon 845 (Octa-core, 10nm, up to 2.8GHz), 8GB Memory + 128GB Storage, Sensors: In-Display Fingerprint Sensor.