This antique bit brace is constructed from a dark hardwood frame, likely rosewood, reinforced with heavy brass plating. This style of tool is frequently referred to as a gentlemans brace or an ultimatum style brace. The frame is fitted with thick brass plates secured by original slotted screws. It features a mushroom-shaped top head and a central rotating waist handle, both made of turned wood that matches the frame. The lower brass plate bears the incised maker mark O. LYON. This identification corresponds to Obadiah Lyon, a prominent toolmaker active in Newark, New Jersey, during the mid-19th century. The tool is finished with a brass chuck designed to accept square-tapered bits.