It not only resizes itself, using the full potential of the well-known jQuery-built Flexslider, but it handles different image sizes depending on devices viewports for faster page loading.

With Truly Responsive Slides Pro, you can now create slideshows that are friendly for search robots and interactive for your users since every slide's content is just plain html (and not an image containing text).

Features:

• any image, standard Joomla article or K2 item sets can be used as source for the slides (selection through custom fields possible),
• source images are used to create the slide's background (including Joomla 3.7+ custom fields and K2 extra fields),
• source content is used as content for a slide, in any position,
• create sliders from 4 different slider types (with or without automatic thumbnails),
• background images are optionally created for mobile devices and speed up page load (breakpoints),
• slide transition options (speed, auto-start...),
• touch-enabled animations,
• add tooltips to slides (in Bootstrap-ready templates),
• use breakpoints for native image swap,
• comprehensive interface when familiar with slideshow software,
• customizable navigation arrows,
• adaptive and SEO friendly content,
• WebP image file support,
• Bootstrap 2, 3, 4 and 5 compatibilities,
• cached and minimized stylesheets and scripts.

More information at https://simplifyyourweb.com/downloads/truly-responsive-slides-pro