The airstrike marker is a small device used to direct TCM airstrikes in Quake II. It appears in three single player campaigns - the original Quake II campaign, The Reckoning and Ground Zero.
It is first introduced in the Outlands where Bitterman uses it to mark a fuel pod for an airstrike. In The Reckoning, Joker calls in an airstrike on a refinery to thwart Strogg fuel production (though he must retrieve the airstrike marker from Gekk raiders first). In Ground Zero, Stepchild uses another marker in the Research Hangar area to assist in the destruction of an anti-air gun.