Hiren's BootCD 115 is an older version of the bootable CD, which was released on August 29, 2016. The ISO file for this version is approximately 586 MB in size.
: To use the ISO, you must write it to a USB flash drive using tools like : Insert the USB into the target PC, restart, and enter the (typically ) to select the USB drive as the primary boot device. Microsoft Community Hub
The original Hiren’s website (hirensbootcd.org) no longer hosts the 15.2 version. However, the community-restored edition is trusted.