Bank 1 is usually the side of the vehicle that the #1 cylinder is on. Bank 2 is the side that the #2 cylinder is on. Sensor 1 will be pre cat sensor and sensor 2 will be after cat sensor.You have :

B1S1 Drivers side pre cat
B2S1 Pass side pre cat
B1S2 Drivers side after cat
B2S2 Pass side after cat.

Post your bin file.