Page Monitor is a free extension for the Google Chrome browser that keeps an eye on changes made on a website. All you do is specify a webpage that you want to track and set how frequently Page Monitor should be checking the webpage for changes (set it to 5 seconds for optimal use). Anytime a page is updated, you will be alerted with a notification on your browser to visit the page.

If you’ve been wondering how some sneakerheads are always able to catch restocks or are always on top of scattered sizes that make their way back to a site from canceled/returned orders, chances are they’re using Page Monitor. You didn’t really think someone was actually sitting there refreshing the page all day, did you? You can get the Page Monitor extension here.