The O'Hara Waltham Dial Company is a historic factory building at 74 Rumford Avenue in Waltham, Massachusetts. The three story brick structure was built in 1897 by Daniel O'Hara, and housed his company, a spinoff from the Waltham Watch Company which specialized in the manufacture of a variety of clock faces. The building has distinctive corner towers with panelled brick surfaces, although these are a later (early 1900s) addition. O'Hara's company operated until the late 1950s; the facility was then used in the manufacture of traffic signals and luggage.