The explanation addresses how to check the inside sealing of the tube.

• Visual Inspection: Remove the cap and observe the tube opening for a sealed foil or plastic membrane.
• Physical Check: Gently press the tube to feel for resistance indicating an intact seal.
• Sound Test: When first opened, a popping or cracking sound confirms the seal breaking.
• Seal Form: Usually, tubes like this come with a foil or plastic inner seal under the cap to ensure product freshness and safety.

This ensures the product has not been tampered with before use.