I spotted this on the tool launch page for the DWST08017 Toughsystem to Tstak adapter - looks like it may play with the non Tstak organisers too : r/Dewalt

DeWalt tstak to toughsystem adaptor

DEWALT TOUGHSYSTEM 2.0 Tool Storage Adaptor, Connecting DEWALT TOUGHSYSTEM 2.0 products to DEWALT TSTAK (DWST08017) : : Tools & Home Improvement

DEWALT® TOUGHSYSTEM® 2.0 Adaptor

DEWALT® TOUGHSYSTEM® 2.0 Adaptor

DEWALT® TOUGHSYSTEM® 2.0 Adaptor

Connect Tough System, Tstak, Pro Containers, and tough cases! Dewalt DWST08017

TOUGHSYSTEM® 2.0 Adaptor

New TSTAK Job Chest : r/Dewalt, tstak

DEWALT TOUGHSYSTEM 2.0 Tool Storage Adaptor, Connecting DEWALT TOUGHSYSTEM 2.0 products to DEWALT TSTAK (DWST08017) : Tools & Home Improvement

Connect Tough System, Tstak, Pro Containers, and tough cases! Dewalt DWST08017

DEWALT TSTAK 4 Wheel Cart DWST17889 - Acme Tools

DEWALT TSTAK Organizer Review Tool Box Buzz

Dewalt DWST83343-1 Tstak™ 2.0 Deep Toolbox With Long Handle

DeWalt TSTAK 2.0 Tool Box 17 1/4 - Screwfix

Dewalt TSTAK VI Rolling Mobile Deep Tool Storage Box Case on