A medical insertion device includes an elongated shaft extending from a proximal end to a distal end and having flexibility sufficient for insertion through a working channel of an endoscope along a tortuous path. The elongated shaft includes a coil extending from the proximal end to the distal end and having a channel extending longitudinally therethrough and a braided portion extending around a portion of the coil, the braided portion including a plurality of lines wound together such that first and second ones of the lines intersect to enclose a predetermined angle therebetween, the angle being between 25 and 55 degrees.