This vintage plaid wool workshirt was made by the Big Indian Shirt company. This is their early yellow and black label with tipis, which was used in the 1920s through the early 1930s. There are two breast pockets. The left one is cut to hold a pen. The collar has a nice shape, with a dramatic undercurve. The tails have gussets.
While most plaid shirts like this were made by outdoors companies like Woolrich, Big Indian was exclusively a workwear company, producing primarily in chambray. Their popularity peaked in the mid 1920s.
Chest (pit to pit): 22″
Shoulder to shoulder: 17″
Sleeve (shoulder to cuff): 23-1/2″