This is one of the best browser extensions for college students ever! If you lack the will power to close your browser and stop watching YouTube or scrolling Instagram before 3am this will fix it! It is light weight and runs great. You can even add a custom URL (Like that assignment your putting off) to reroute to if you try and open a blocked page. The military time set up is a little confusing for some people but nothing you can't Google. Overall a great add on. I will not run Firefox or Chrome without it.