Bootstrap is a CSS framework from Twitter with many features which help web development progress more quickly. If you are a designer which design a web project base on Bootstrap, Bootstrap V3.0.0 UI kit PSD from dribble is a good template to use.
In my opinion, this UI kit is lack of some elements, but it is enough for a freebie. Thanks Monsieur Cédric who published this PSD. Grab the package here. It is free to download.