New 12 zone install... But i only have 9 Sensors and 10 Wired... lol

So i received my boards yesterday! Nate awesome job man! Install was a breeze....  However when i was breaking my zones apart, they had all 9 ingress and egress points in 4 zones, I found 10 wired sensors. I only have 9 ingress and egress points between windows and doors! Im thinking my sliding door has a sensor on each side? but usually they are in the center of the door... 


Anyways... i have the panels mounted wired and setup. My biggest question is Which size Fire Tablet does everyone recommend for Panels? 7" 8" ? 

literally Unknown Sensor that shows Closed...


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