This product is a coaxial catheter with a balloon near the distal end. It is intended for providing a fillable portion of a known diameter and length at the recommended pressure. The proximal end of the catheter has two handles with independent lumens. The luer lumen in the middle delivers the delivery balloon dilation catheter through the narrow area to be dilated by a guide wire, and the outer lumen on the other side is used to fill and retract the balloon. The catheter is coated with a hydrophilic coating on its outer surface to reduce friction during operation. The tip of the catheter is tapered to facilitate the pushing of the catheter through the narrow area. The developing ring at the end of the catheter facilitates the placement of the balloon portion of the catheter while under X-ray fluoroscopy. The delivery balloon dilatation catheter, in combination with the micro guidewire and the guide catheter, can reach the position of any diseased vessels within the corresponding diameter. After the lesion is dilated by inflating, the unloading pressure can be smoothly withdrawn from the body.