Advanced Knee Replacement



The Advanced Knee Replacement is a device used in Portal to keep Test Subjects from injuring themselves due to falls from great heights. They protect the player from falling damage at any speed, even from terminal velocity. After. They are superseded in Portal 2 by the Long Fall Boots.

Trivia

 * The idea for the Advanced Knee Replacement was recycled from a cut character from Half-Life 2, the Combine Assassin.