The spacesuits are mandatory for the Captains to survive on the Planet of the Pikmin, and are also their main defense against environmental hazards and enemy attacks. The suits include a transparent helmet, typically shaped to accommodate the size of the wearer's head, and has an antenna with a light on the end that serves as a beacon, as well as an alternate light source. There is a pack affixed to the back of the suit which presumably contains the life-support system. Each captain has a differently sized and colored suit. In Pikmin 1, Olimar's suit can only sustain him for 30 days before the life-support functions fail.
The suits will spark when damage is taken from an enemy or hazard, and the health meter in the bottom-left corner of the screen will decrease accordingly. When the meter has been reduced to less than half, it will start to flash and a beeping noise will resound. Any damage taken can be repaired by ending the day and going into the next morning, finishing a cave, or by standing in the light of the Dolphin and pressing A in the first game. This will not work with the Ship in Pikmin 2, so the player must survive until the start of the next day. However, if one captain should take too much damage and fall in battle, the player can continue the day as the surviving captain.
When a captain whistles, the antenna will emit rings of light which spread out at the point where the pointer is. Each captain's whistle has a different sound.
In Pikmin 3, the spacesuits worn by Alph, Brittany and Charlie are nearly identical to Olimar's, but feature small pea whistles attached to the front of their helmet. The area below the collar is also colored the captains' main color.