zeroHero WDT Needle Distribution ToolzeroHeros magnetic WDT engineered to break clumps and kill channeling before you tamp. Six 0. 6 mm 304 stainless needles rake and fluff grounds to erase clumps and pockets, giving you a level, airy bed that reduces channeling. The tool docks on its weighted stand between shots and snaps magnetically to any metal surface when space is tight. Needles taper to a fine point for gentle, low resistance stirring; the aluminium body feels solid and balanced