OCX Featured Slider - a slider module that is exactly you need to promote your products adding banners.
Add banner that describe your offer and just choose product related with banner.
You can check the Shop DEMO: http://www.demo3.oc-extensions.com/modules/index.php?route=product/category&path=18
and the Admin DEMO: http://www.demo3.oc-extensions.com/modules/admin
user: demo pass: demo
Check our OpenCart GDPR - General Data Protection Regulation extension here: