Rangers regularly operate in teams of five, six or seven, with a special sixth Ranger frequently staying or going to the group, sometimes a core team of three will then be joined by additional Rangers. The Ranger's suit is almost always the same color of his Zord, his civilian clothes and energy of its powers (such as Sky Blue Ranger was at the beginning and their areas of strength were the same color). Rangers may be nominated by their respective colors, such as Red Ranger, Blue Ranger, etc.. but numbers or other names may also be used. Usually no more than one Ranger of a given color on a computer, but the exceptions to this rule, generally, get alternate names. The team's costumes are almost identical apart from color, helmet design (most notably the shape of the opaque visor) and perhaps a numerical designation, any of the Rangers have scheduled additional modifications to further suit. In some generations, the Rangers had the ability to open the display when no one was opaque, as the case of Lightspeed Rescue and Ninja Storm.