New Flush knife with improved sheath thickness and length has been released lately. In the first part, by explaining each features and the history of the development of ESD knifes and design philosophy of the Flush Knife, you can understand how to use Flush Knife effectively. This is the device which can do incision, dissection, hemostasis, and also equipped with a water jet function, which was the first invention to equip on ESD device in the world. Also, the improvements and usefulness of the new Flush knife will be introduced. By improving sheath thickness, the suction performance has been significantly improved. In addition, the angle operation gets easier, insertion becomes smooth, and the frequency of kink has been improved. I believe you can understand the leading edge innovation of ESD knife through this lecture. In the second part, from numerous experiences of ESD cases, various case videos including latest ones will be introduced. For this session, I focused on three unique technique, “sliding”, “scooping”, and “tapping” technique, which can be used during dissection by Flush Knife. I hope that this lecture and video case introduction will give you an idea that you can use it practically from tomorrow in your daily procedures.