A medical device for vessel occlusion, the medical device including an elongated body having a distal end portion, a proximal end portion, and a lumen disposed therethrough, an balloon disposed at the distal end portion of the elongated body, the balloon in fluid communication with the lumen. The finger grips make the slide clamp easier to use while reducing the risk of error. Then, an image is captured by an operating device in the direction of a position pointed by the operating device. The winding axis for the main winding is at right angles to the winding axis for the control winding. In the opening path of the interlocking tongue, a blocking element is provided, as a result of which the interlocking tongue can only be set to the opening position after removing the blocking element by means of a suitable tool. If so, the terminal server sends a fragment index to the client identifying the entry in the fragment cache for that fragment.