Sub Pen
General Information
The Sub Pen is a 2x2 Base Facility. You require one Sub Pen for every Flying Sub you own or are in the process of constructing.
The Sub Pen serves as an access point for encroaching alien forces. The Sub Pen cannot be destroyed during a Base Defense mission.
Statistics
Construction Time: 25 days
Construction Cost: $200,000
Maintenance Cost: $25,000/month