Mozilla Labs testing  some experimental features and new ideas for Firefox 4 Beta, these experiments are released and available as add-ons from Mozilla add-ons.Mozilla Labs released Lab Kit which automatically adds, removes and updates these experiments without any interaction from the user.

Mozilla Labs Lab kit

Mozilla Labs Lab Kit is a restartless add-on .You need to be using latest Firefox 4 Beta or nightly build  to install this add-on.

Lab Kit will securely install add-ons that have been reviewed and approved by Mozilla Labs team.Test Pilot ,Prospector, Speakwords and Contacts are initial experiments in the lab kit , so these will be installed when you installed Lab kit for the first time.

If there are any major updates in Lab kit you will be notified about this in Firefox with a notification with list of changes and contents included in the Lab Kit.

Install Mozilla Labs Lab kit