This is an overdyed US military sleeping shirt from the 1950s.
With its asymmetrical rounded collar and wide silhouette, it doesn't have the feel of a traditional sleeping shirt at all, but rather has the feel of a contemporary designer brand.
Being an old item, the fabric has a very sturdy feel, but the black color achieved through post-dyeing gives it a modern look.
CONDITION : DEAD STOCK (Over dyed)
*This is a dead stock item, so there may be some dirt or fraying due to storage over time. Please be aware of this before purchasing.