Block Site (formerly known as Stop Social Media) is a simple Chrome *extension that improves your productivity by blocking the access to *time-consuming websites (like during the working hours) as you specify in *Options. Block Site is by default disabled and doesn't block any *website until you say so in Options.
To open Options, right-click on the Block Site icon in the toolbar (looks like a letter B) and choose Options from the menu.
The sites you decide to block to boost your productivity, is up to you. Here's an example:
facebook.com
instagram.com
youtube.com
twitter.com
reddit.com
See Options to configure.