A medical insertion device (100) includes an elongated shaft (101) 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 (102) extending from the proximal end to the distal end and having a channel (106) extending longitudinally therethrough and a braided portion (110) extending around a portion of the coil, the braided portion including a plurality of lines (112,114) wound together such that first (112) and second ones (114) of the lines intersect to enclose a predetermined angle therebetween, the angle being between 25 and 55 degrees.