From the designer:

This is a custom insert that I have designed to fit your Milwaukee Packout to store your M12 Nibbler and accompanying kit. It specifically fits theMilwaukee 48228435 PACKOUT Compact Organiser.

The specific M12 Nibbler that this is designed for is model M12FNB160, link is provide here:https://www.milwaukeetool.com.au/power-tools/metal-working/nibblers-and-shears/M12FNB160.html

Wenow 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.