From the designer:
This is a custom insert that I have designed to fit your Milwaukee Packout to store your M18 Multi-tool and accompanying kit. It specifically fits the Milwaukee 48228435 PACKOUT Compact Organiser.
The specific M18 Multi-tool that this is designed for is model M18BMT-0, link is provide here: https://www.milwaukeetool.com.au/discontinued-products/M18BMT-0.html
We now offer latches to identify which tool is in which case. Latches are offered at a discount if purchased with a matching insert and are sold by the pair.