An endoclip is a metallic mechanical device used in endoscopy in order to close two mucosal surfaces without the need for surgery and suturing. Its function is similar to a suture in gross surgical applications, as it is used to join together two disjointed surfaces, but, can be applied through the channel of an endoscope under direct visualization. Endoclips have found use in treating gastrointestinal bleeding (both in the upper and lower GI tract), in preventing bleeding after therapeutic procedures such as polypectomy, and in closing gastrointestinal perforations. Many forms of endoclips exist of different shapes and sizes, including two and three prong devices, which can be administered using single use and reloadable systems, and may or may not open and close to facilitate placement. Structure and function The endoclip was first described by Hayashi and Kudoh in 1975, and was termed the "staunch clip". Initial attempts to incorporate the clip into applications in endoscopy (such as clipping bleeding blood vessels) were limited by the applicator system of the clip. However, by 1988, an easy to use applicator delivery system was developed, and a functional reloadable endoclip system was described. This consisted of a stainless steel clip (of size approximately 6 mm long and 1.2 mm wide at the prongs) with a metal deployment device (that could be used to insert the clip into the endoscopic camera, and deployed outside the camera) enclosed in a plastic sheath. These clips were initially reloadable. Endoclips in use today have a variety of additional shapes and sizes than the original. Clips with two and three prongs (TriClip, Cook Medical) have been described and used for various applications. Rotatable clips have been devised to improve localization of deployment. Also, clips that open and close (as opposed to single-deployment) have also been developed (Resolution Clip, Boston Scientific), and also facilitate the appropriate location of deployment. When a treatable lesion is identified on endoscopy (such as a bleeding vessel), an endoclip can be inserted through the channel of the endoscope until the sheathed clip is visible on the endoscopic image, and the handle for deployment handed to the nurse assistant. The clip is unsheathed by retraction at the handle, positioned, and "fired" by the assistant to treat the lesion. Applications of endoclips Gastrointestinal bleeding Endoclips have found a primary application in hemostasis (or the stopping of bleeding) during endoscopy of the upper (through gastroscopy) or lower