Blank Seattle Mariners jerseys in throwback 80 & 90's styles. Plain Mariners baseball jerseys are available in youth to adult 3XL sizes and are blank replicas of what the M's wore on the field. Plain Seattle Mariners jerseys can be decorated with sewn tackle twill, screen printed or sublimated team names, logos, numbers and player names. Request a quote for factory direct decoration for a pro baseball look today.