bootstrap-select

Bootstrap-select is a jQuery plugin that overhauls select elements to improve their appearance and expand their functionality.

https://cdn.bootcdn.net/ajax/libs/bootstrap-select/1.4.1/bootstrap-select.css
https://cdn.bootcdn.net/ajax/libs/bootstrap-select/1.4.1/bootstrap-select.js
https://cdn.bootcdn.net/ajax/libs/bootstrap-select/1.4.1/bootstrap-select.min.css
https://cdn.bootcdn.net/ajax/libs/bootstrap-select/1.4.1/bootstrap-select.min.js