Metal Kettles Repository Kodi 16 is an all-in-one Kodi from which you can download many popular add-ons such as Sports Mix, UK Turk Playlist, UKTV Again, Movie Mix, and many more.
Like the installation procedure of other repos, it requires a website URL to be added to Kodi which would indicate where all files are stored.
Guide & Install For Metal Kettles Repository Kodi 16
Kodi main menu go to System–>File manager
Next click on Add Source 
Select the option NONE
The updated version of Metals Kettles Repo has moved to Fusionhttp://fusion.tvaddons.ag/kodi-repos/english/
Copy and paste the URL: http://kodi.metalkettle.co/
Next name the media source as Metal Kettles in the blank box and click OK
From the main Menu go to System–>Settings
Click on Add-ons.
Then select Install from zip file.
From the box that will slide open, find and select Mettle Kettle and click it.
Next, click on repository.metalkettle-1.7.1.zip (Install the newer version if possible.).
After the repo has been installed, a pop-up message will appear on the bottom-right of the screen saying Metal Kettles Add-on Repository updated.
Now your Mettle Kettle Repo will be installed.
Steps To Install Mettle Kettle Repo Add-ons
For installing add-on from the Repo go to System–>Settings–>Add-ons–>Install From Repository.
Scroll down to find and select MettleKettles Addon Repository
Choose the section the plug-in would fall under. The most popular is Videos.
Choose the add-ons of your choice and click Install.
After a plugin installs you can locate it from its respective section the plug-in belongs to in the main menu. This video section would be located from the main menu Video–>Add-ons