Abstract: A dual refill containing variable refill positioning writing instruments utilizing cam followers attached to two refill members and oppositely threaded spiral cam grooves within which said cam followers ride. The writing instrument includes an inner tubular shell having two spiral cam grooves each located substantially about one-half of the circumference of said shell and longitudinally displaced from each other and an outer tubular shell having two spiral cam grooves located around substantially one-half the circumference of the shell and longitudinally spaced from each other with each of the cam grooves corresponding with but oppositely threaded in respect to the inner shell spiral cam grooves. The inner shell nests within and is rotatable with respect to the outer shell.