The Black Hole Duffel 45L Dufflebag from Patagonia.
If only your tool chest were as tough as this duffel. Highly weather-resistant, this is the smallest Black Hole Duffel that's designed to protect your gear from rough handling and miles of traveling abuse. Its U-shaped lid allows quick access to the main compartment, while two zippered internal mesh pockets keep small items organized.
The padded bottom panel adds structure and helps cushion the load when your duffel gets the baggage-handler treatment. Carrying options include webbing handles with a snap closure and haul loops at either end that facilitate linking multiple bags. Four daisy chains let you lash additional gear to the outside.