Wings of Glory: ACE Scout Special Damage Markers

From the Publisher:

Not only do the ACE Scout Special Damage Markers markers add a lot of visual impact to your game, they are also function in that they help keep track of how long your plane is on fire or smoking. Made in three parts, simply remove one part at the start of each turn when you draw your damage cards (for fire) or at the end of each turn for smoke. Once the last part has been removed, the special damage no longer applies.

The laser cut and engraved markers simply slide over one of the altitude pegs.