king pin designs which further provides improved contact with the trailer king pin and which provides structure for visually observing the relative position of the extension adapter and the hitch assembly located in the bed of the towing vehicle the fifth wheel extension adapter comprises a vertical column a bottom portion designed to releasably connect to the hitch assembly and a top portion designed to adjustably mate to a wide range of trailer king pin designs the fifth wheel extension adapter is further designed to be easily attachable and easily removable permitting the operator maximum flexible use of the towing vehicle as well as the ability with only one extension adapter to tow the widest variety of fifth wheel trailers an additional improvement included within this invention is a mirror attachment which provides the structure for the operator to observe and guide the extension to mate with the hitch assembly application_number US 79508697 A description fig1 shows the detachable extension adapter invention 101 designed to convert a fifth wheel trailer 901 to a gooseneck trailer permitting the acceptance of the ball hitch 903 at bed level in the towing vehicle 902 the extension adapter 101 is composed of a vertical column 102 a top portion 103 and a ball coupler assembly 119 the vertical column 102 provides extended structural support between the fifth wheel trailer 901 and the ball hitch assembly located in the bed of the towing vehicle 902 the vertical column 102 is preferably made of quarter inch plate structural steel formed to a 180 degree columnar shape or a shape which is somewhat similar thereto with two gussets 505 and 506 formed at the back side 122 of the vertical column 102 the gussets 505 and.