A hub defines a lumen with a longitudinal axis along the length of the hub. An outer surface of a distal portion of the hub tapers inwardly toward the longitudinal axis as the distal portion extends distally. A strain relief includes a proximal portion configured to receive the distal portion of the hub. The strain relief defines a lumen that substantially aligns with the hub lumen when the proximal portion receives the hub. The hub and/or strain relief are configured to be fixedly attached to a catheter body such that a catheter body lumen substantially aligns with the hub lumen and the strain relief lumen when the strain relief receives the distal portion of the hub. Outer surfaces of the strain relief and hub define substantially similar distances to the longitudinal axis along an interface between the two outer surfaces when the strain relief receives the hub.
