These pipes are provided with V shape ribs on its exterior surface. Special design of this structure with fine slots provided on pipe, prevent entry of even small particles and hence permeability of the screen gets properly maintained. These pipes are generally used in combined wells or used for specific formation where normal screen pipes does not work, e.g. fine sand. These pipes are provided with threaded joints with one end of the pipe is male threaded and another end with female threaded socket.