Cotisen Implant Impression Trays Set is composed of external and internal trays. The external trays are made of rigidly engineered plastics ,which provides enough support for the impression material . The inner tray and the external tray can be mechanically interlocked together, which can effectively lock the impression material in the dental tray . The supporting side wall area of inner tray exist pores , which can effectively prevent demoulding. There are 18 detachable fan-shaped plates at the bottom of the arch area,which can be removed quickly and conveniently according to the tooth position. The arch area is covered with an easily penetrating film that takes the mold accurately and cleanly. The material will not overflow .