These strapping men were employees of the Wilcomb Machine Company, a firm that made industrial sewing machines in Norristown.
The company was managed by J. Frank Wilcomb who had several patents on sewing machines, such as the two pictured here.
And here’s a neat advertisement from a 1910 trade paper:
The factory stood at Washington and Franklin Drives in Norristown. I can’t tell when the factory closed down, but by 1920, Frank Wilcomb had moved on and founded another company in Rhode Island.