Tribes: Ascend/Stealth Pack
"When activated, the Stealth Pack renders you invisible to all enemies. You will appear briefly when taking damage, firing a weapon, or at speeds over 150kph."
The Stealth Pack is one of the default unlocked packs for the Light Armor. This pack makes the Light Armor completely invisible, whereas previously there was a faint shimmer, and the skis would show a thruster trail. The Stealth Pack will be disabled if the player takes damage, fires a weapon, moves at a speed over 150 km/h, or is within range of a jammer. The Stealth Pack uses 6.5 energy per second.