Z-4190 bubble shield

Summary
The Bubble Shield is a Covenant defensive device used primarily by Brutes. The shield itself is a Geodesic dome (of sorts) made of tessellating hexagons. The bubble shield projects a defensive field around the user when deployed that blocks all projectiles. Vehicles and players however, are still able to pass through it. Gameplay shown at E3 2007 shows that, out of the enemy NPCs, at least Brutes will make use of the bubble shield. This "object" is one of the few equipment items, next to the Trip Mine, Power Drainer, Radar Jammer and Portable Gravity Lift. It was first seen in the Halo 3 "Starry Night" CGI Trailer.

Starry Night Commercial
This incarnation of the Bubble Shield was more cylindrical and had a safety cover on top of the "grenade", which could be flipped up to expose the red activation button. After that, it emitted a charging sound and upon resting on the ground for a short time, created the shield. Since Bungie stated that all assets in the commercial were produced by them, it is safe to say this device will show up in the game. It should be noted, however, that the "Starry Night" commercial is CGI [] and the appearance may not be too accurate.

Is Quisnam Protero Damno" Multiplayer ViDoc
A player deployed this version while running from Battle Rifle fire. The shield successfully absorbed all projectiles and grenade explosions fired. It appeared to be a large sphere-shaped object. It could roll around while activated. It appeared much larger than its first appearance in the Starry Night commercial. This version of the Bubble Shield is seen used in the Alpha-stage Halo 3 footage for multiplayer. The Bubble Grenade rolls down a hill as the Spartan-II concealed in the sphere back-pedals away from an enemy. Information later released by Bungie, however, stated that the sphere would rest on the ground and the Spartan II would need to stand still to enjoy its effects.

Halo 3 Multiplayer Beta
The bubble shield appears and functions differently from both of its previous appearances. This version is similar to the Starry Night appearance. In the Halo 3 Beta the Bubble Shield is stationary and does not roll as it did in the ViDoc. The shield itself has remained the same otherwise. The Bubble Shield generator looks significantly different in the beta version than it does in both the commercial and the ViDoc. The generator has four legs and can be destroyed from within the shield, collapsing it prematurely.

Throughout all these physical changes, the shield itself has stayed the same with the hexagon patterns and transparency.

Trivia

 * Frankie has said that the shield is ONI tech..
 * This shield resembles the description of the Onyx Sentinel shields in the Eric Nylund novel Ghosts of Onyx.
 * New information says that the bubble shield is now larger, but lasts for a shorter period of time.