whats the difference between these 2 cameras?

[HMS]

• Starlight IR Dome w/SD, External Audio & Alarm (2.7mm-12mm): IPC-HDBW5231E-Z
  
• Starlight IR Dome w/SD, External Audio & Alarm (2.7mm-12mm): IPC-HDBW5231R-Z

so far all i can see is one has a little bit more range on the tilt and rotation and the overall size of the camera and housing is bigger on one compared to the other..

What an i missing?

 

[cb8]

Besides the dimensions, the specs list the IPC-HDBW5231E-Z with three IRs and a higher max power consumption, so presumably it has stronger IR.