The Milwaukee M18 FUEL™ 1/4” Lockbolt Tool with ONE-KEY™ Hucktainer® Fastener Adapter is made from proprietary steel to ensure durability and provides the capability of installing 3/8" Hucktainer Fasteners by making a simple and quick swap with the Adapter included on the M18 FUEL™ 1/4" Lockbolt Tool with ONE-KEY™. This item is compatible with the MILWAUKEE® M18 FUEL™ 1/4" Lockbolt Tool with ONE-KEY™ (sold separately).