Which POE module?

BPI-M2+/BPI-M2 Zero/BPI-P2 Zero
1

I am using Cisco Catalyst 2960S-48LPS-L - it “supports both IEEE 802.3af Power over Ethernet (PoE) and IEEE 802.3at PoE+”

I have 4x Banana Pi BPI-P2 Zero.

Which voltage do I need? For RT9600 POE Module, there are 4 voltage output options: 3.3V, 5V, 12V, or 24V.

2

you need chose 5V for BPI-P2 Zero

http://wiki.banana-pi.org/BPI-9600_IEEE_802.3af_PoE_module