Clip device

A method for treating tissue, comprising:

• inserting a clip device, in a closed configuration, to a target area within a living body via a working channel of an endoscope, the clip device including a restraining tube, a first arm and a second arm movably received within the restraining tube;
• moving the clip device from the closed configuration to an open configuration in which the second arm is moved laterally away from the first arm and a second distal end is moved distally past a first distal end of the first arm;
• in the open configuration, moving the first arm within a first movable range, and moving the second arm within a second movable range, and in a fully open configuration, the first movable range is smaller than a second movable range in a longitudinal direction of the restraining tube;
• grasping a first tissue along a first side of the tissue with the first distal end of the first arm;
• grasping a second tissue along a second side of the tissue with the second distal end of the second arm, the second side opposing the first side;
• and
• moving the clip device toward the closed configuration, in which the second arm is drawn laterally toward the first arm and the second distal end of the second arm is drawn proximally toward the first distal end of the first arm so that the second tissue is drawn toward the first tissue, thereby closing the tissue.

A clip unit comprising:

• a clip portion including,
• a tube;
• a first arm including a first proximal end and a first distal end, and the first arm is configured to move within a first movable range in a longitudinal direction of the tube relative to the tube;
• and
• a second arm including a second proximal end and a second distal end, and the second arm is configured to move within a second movable range in the longitudinal direction relative to the tube, and
• wherein the clip portion is configured to be switched between an open configuration and a closed configuration, and
• in the open configuration, the first distal end is located at a first distal most end within the first movable range, and the second distal end is located at a second distal most end within the second movable range, and the second distal end is disposed more distally than the first distal end.