Chemical light stick

Chemical light sticks, also known as "chemlights", are plastic tubes containing two isolated elements that when combined, are capable of producing light through chemoluminescence.

Background
They are currently used by the UNSC. When lit, they glow a sickly yellow color, and are used primarily to mark areas or as emergency lighting. The UNSC also utilizes glow rods for similar purposes.

Chemical light sticks were used by Spartan Red Team to provide lighting in CASTLE Base on Reach, and later during Operation: FIRST STRIKE on the captured Spirit dropship.

Chemical light sticks were also used by Recon Team Bravo during a night operation.

Major Vaughan of the ODST kept spare chemical light sticks on his person for situations where other methods of signaling were unusable or unsafe.

List of appearances

 * Halo: First Strike
 * Halo: Reach
 * Nightfall
 * Halo: Tales from Slipspace
 * Undefeated
 * Halo Wars 2