Thin Blue Line USA Official Site Shop Gifts, Flags, & Apparel Thin Blue Line Concealed Carry Bag Rothco Black Concealed Carry Bag w Thin Blue Line Concealed Carry Purses CCW Purses Nine Line Apparel Thin Blue Line USA Official Site Shop Gifts, Flags, & Apparel. The Thin Blue Line is a symbol of respect and support for Police and Law Enforcement Officials; show your support with the Thin Blue Line Concealed Carry Bag. This concealed carry shoulder bag is made from durable 600D polyester with PVC coating and polypropylene webbing. The tactical bag features carry handles, as well as an adjustable and removable shoulder strap and 2 front D rings. Thin Blue Line bag has optimal storage options, with a large main compartment, a large side pouch with flap and quick release buckle closure, a large side zippered pouch with exterior MOLLE attachments, 3 zippered pouches in front, and a rear zippered pouch with the loop side of a hook and loop for concealed carry attachment.