From Classified Intel Report 097/5b
In spite of extensive scouting of the aliens' base, we have come to no significant conclusions about the purpose of individual structures, although some tentative identifications have been advanced. The defensive structures, however, have been extensively studied and are centered around a structure we have tentatively called a "force wall," a barrier of energy pulses that stops both physical objects such as kinetic weapon projectiles, as well as beamed weapons.
Finger and Toe Models announces the release of the 28mm cardstock Alien Base: Force Wall. The kit has three components identified by Allied Intelligence teams to build your defenses – a force wall generator, a force wall transmitter in three colors, and a gun tower.
Remember, every Finger and Toe model comes with smoosh assurance: if ya'll smoosh your Alien Base: Force Wall, a new one waits your summons from hard drive and printer.
Alien Base: Force Wall is available from rpgnow.com or wargamevault.com for $6.00 USD.