STACK PACK COMPATIBLE - Fits with select FLEX STACK PACK tool boxes and organizers. Ideal for the Medium Tool Box (FS1102), Suitcase Tool Box (FS1103), and Organizer Box (FS1301) MAXIMUM ACCESSIBILITY - Hang power tools from the sides of your storage toolboxes for easy access on the job DURABLE CONSTRUCTION - Made from durable steel and two-piece construction with a slip-resistant design to securely hang tools or batteries CUSTOMIZED EXTENSION - Pre-drilled holes offer customized extension with clamper hooks QUICK INSTALLATION - Easily screws to tool box for durable, secure connection WHAT'S INCLUDED - (2) FLEX STACK PACK Side Tool Rack Rails, (4) FLEX STACK PACK Corner adaptors, fasteners for installation FULL RANGE COMPATIBILITY - STACK PACK toolboxes, organizers, accessory cases, and toolbox attachments are endlessly configurable across the full STACK PACK system