Authentic Littmann stethoscopes have a serial number engraved on the chestpiece.
The original Littmann’s cover is really beautifully made. A seal could be present. A well-shaped protection for your stethoscope is within, along with extra earpieces and instructions.
The soft and retracting ear pieces from Littmann offer outstanding comfort and fit to the ears. The sound of the environment is better sealed off. If the earpiece is hard, strong, or fragile, it is undoubtedly a copy.
The diaphragm moves together with two connected ear pieces when they are forced against one another. This is present in the original stethoscopes, but very few high-copy models can pass this test.