Plugin supports 4.10-4.70 versions.

https://www.foxnetsoft.com/content/files/foxnetsoft.pagespeedtools_410.zip
https://www.foxnetsoft.com/content/files/foxnetsoft.pagespeedtools_420.zip
https://www.foxnetsoft.com/content/files/foxnetsoft.pagespeedtools_430.zip
for 4.40, 4.50, 4.60, 4.70
https://www.foxnetsoft.com/content/files/foxnetsoft.pagespeedtools.zip

Update.
Steps:
1. Backup your plugin folder
2. Copy all files to the Plugins folder of nopCommerce (all files!!! It's a very important).
3. Restart your site.
