Abstract: In a sidepocket mandrel for use in a well tubing in which the valve pocket is positioned inside of the mandrel body beside an opening with a deflector guide connected to the pocket and having a pair of rails for allowing the entrance of flow control devices into the pocket but preventing the entrance of open bore tools into the guide path and a locking lug secured to the deflector guide, the improvement of providing the longitudinal outer edges of each of the rails adjacent the open bore with a deformable lip protruding outwardly from the rail in which the lips are bent outwardly towards and against the inside of the body for preventing wirelines of well tools from catching between the inside of the body and the rails. The lips may be formed in the rails by either longitudinal recesses positioned along the edges on either the inside or outside of the rails.