Aside from weapons, Nukem can also find 'medkits' to heal himself whenever the player chooses. Steroids make the player move faster, as well as removing the effects of the shrink-ray. Nightvision goggles allow players to see enemies in the dark. The "HoloDuke" device projects a fake hologram of Duke that can be used to trick enemies. Protective boots allow the player to cross dangerously hot or toxic floors. For underwater scenes, scuba gear (an aqua-lung) can be used to let Duke breathe. One of the favorite items is the jetpack which allows the player to fly up in the sky, often to reach hidden weapons or extra health. Many of the secret items such as the jetpack, the scuba gear and the night vision goggles only last for a short time. Weapons also have a limited number of ammunition.