308 in operation a proximal end of the main branch guidewire 306 is fed into the main branch distal exit port 110 and exits through the main branch proximal exit port 108 a proximal end of the side branch guidewire 308 is fed into the distal end 103 of the catheter 102 and exits through the side branch exit port 106 the catheter 102 is urged through the vessel system 300 and follows the side branch guidewire 308 the movement of a catheter within a patient 39 s vessel system is well known in the art and will not be discussed in detail here as shown in fig4 b the catheter 102 follows the side branch guidewire 308 into the side branch vessel 304 as the catheter 102 turns or is directed into the side branch 304 the main branch guidewire 306 will begin to bind on the catheter 102 this binding or resistance is detected by the operator of the delivery system and is used to position the distal end of the catheter 102 at the desired location within the side branch 304 as can be seen a distance from the distal end 103 of the catheter 102 to the main branch distal exit port 110 will determine how far into the side branch 304 the catheter 102 and therefore the device.