Flashlight

The Flashlight is a portable hand-held electric light used to better see in the dark.

Original Timeline
Flashlight is an item in the the Tomb Raider: The Last Revelation Lost Library early demo. The Flashlight was featured on the front cover, and mentioned in some of the backcover as well. The flashlight would have been used to light dark areas. It could also be combined with some weapons.

Lara uses the flashlight in an prerendered FMV to read inscriptions on the wall of Tomb of Semerkhet.

Legend Timeline
Flashlight is used in the Legend trilogy as an automated light source assigned to a hotkey, and with a timed duration, that recharges when not in use.

In a Wii version on Tomb Raider: Anniversary however, the flashlight is a selectable item, that is held in Lara's hand and directed with the Wii remote.

Survivor Timeline
In the Survivor trilogy, Flashlight makes a first appearance in Rise of the Tomb Raider DLC Blood Ties where it is one of the collectible relics. On it Lara notes to remember to pack this for next adventure. And so she does, as in the sequel Shadow of the Tomb Raider, the flashlight replaces the glow sticks as a light source. The flashlight is automatic and lights up on its own in dark areas.