OS X 10.11 or better known as El Capitan is an operating system released Sept 30th 2015 as the direct successor to OS X Yosemite, the very first Mac OS to use the material design language as known today.
Attached is a zipped copy of the Installer App as originally downloaded off the App Store and thus contains all necessary components for an upgrade or standalone install on a supported Mac.
Included file is in the 7zip format and requires 7zip to extract
NOTICE: This is an EXACT copy of the install application as provided by Apple Inc. for free on the Mac App Store and is licensed for use on ANY SUPPORTED Mac free of charge.