This insert comes in two configuration: one that holds up to six (6) and one with up to twelve (12) M12 batteries in the Milwaukee Packout Medium Tool Box (48-22-8424).  Insert fits in the divider grooves of medium tool box and are a great way to keep your batteries stored with your go-to M12 tools.  The single sided (six battery holder) also serves as a divider and fits snug against the stock interior trays/bins.

Available in Red, Black, or Gray.