Abstract: A double lumen tubing which is adapted for use as a catheter. The tubing accommodates multiple sized guidewires and has increased resistance to kinking. A lumen wall divides the outer tubular wall into the two lumens and has a central arcuate portion shaped to allow insertion of relatively large guidewires through one of the lumens, while still leaving space for smaller guidewires through the other lumen. Resistance to kinking is increased by varying internal diameters or axes of the interior lumen walls to increase the wall thickness of the tubing in selected areas, and by varying the thickness of the wall that divides both lumens in the middle or where the dividing wall meets the outer tubular wall.