Scroll Progress Bar displays a visual indicator of your location on a page. You may also activate smooth scroll.

Scroll To Top Button - Awesome.

WordPress custom scrollbar is highly customizable WordPress plugin. Features include vertical and/or horizontal scrollbar(s), adjustable scrolling momentum, mouse-wheel, keyboard and touch support, ready-to-use themes and customization via CSS.

A simple, better looking scrollbar for your website.

Adds a custom scrollbar to specified HTML elements.