Adult Rectangular Bag 30 Degrees Collegiate Navy. Weâ??re constantly testing our products in the worst conditions all around the world to make our products perform even better. Explore how we test, and share your toughest moments of testing with us in the reviews below. The Adult Rectangular Sleeping Bag has a lightweight durable 50D polyester taffeta shell, soft polyester pongee liner thatâ??s warm to the touch, and is filled with a 4-hole hollow fiber polyester insulation to rate this bagâ??s comfort level at 30 degrees F.