It looks like an aurora borealis in there!
In third season episode That Which Survives, alien sabotage of the matter-antimatter integrator forces Scotty to use this tool in a risky attempt to manually interrupt the fuel flow to the runaway warp engines, with only minutes remaining until the ship is destroyed.
Four-piece machined aluminum construction, with removable and reversible endcap (that won't get stuck), clear acrylic guide fins, and transparent red acrylic and metal details on the head.
By gaston.
