Klite Codec packs are a bunch of codec that helps in opening, playing various file formats on your windows media player. For example, if you want to open MKV file or other video format which is not supported by windows player then you can install k-lite codec pack as it has a support for hundreds of file extension enhancing the capabilities of opening unknown file formats.
With lots of new audio, video extensions released frequently, it is recommended to download the latest K-lite code pack. For some time, klite was in 4.X version and recently the new update of K-lite 5.0 was released. This mega pack is quite similar to older version expect the special media info and tweak tool features that can come in handy at times.
Here are few alternate links for the download. Choose any of the site and download directly.
Note that all the version are 3.7mb in size and these Klite mega packs are free, works with Windows Vista, XP and 2000 2003 OS platform.