Regenerator

The Regenerator is a piece of equipment used in Halo 3. In terms of function, it may be related to the Sterile Field Generator.

Background
The Regenerator, like the Bubble Shield, emits a small, green field of energy which restores a player's shield as well as well as anybody near you, as well as an enemy, for 15 Seconds. There is, however, a small delay before beginning the recharge, which means the player is still vulnerable, and you are vulnerable to weapons which can kill the player in one shot. It also is less effective if a lot of enemies are firing at you. It is the exact opposite of the Power Drain and when it is used in the same area as a Power Drain, the Power Drain overpowers the Regenerator. Other ways in which the Regenerator is dissimilar from the Power Drain is that the Regenerator remains rooted in the same spot where it is deployed while the Power Drain can move around.

Trivia

 * Brutes have a tendency to throw out Regenerators to help repair the impact diffusion feature of their Power Armor.
 * If you stand near a Regenerator, you will hear your heart pulsating. The same applies in Halo: Combat Evolved where when you have one bar of health you can hear your rapid heartbeat.
 * When in a Regenerator with an opponent, melee, don't shoot, it's a much more effective way to take down your opponents.
 * If you stick a Spike Grenade to a Regenerator it will spin around with it.