A stent delivery system can include an elongate core member sized for insertion into a blood vessel. The core member can be configured to advance a stent toward a treatment location in the blood vessel. The core member can include a longitudinally extending tube having a helical cut extending along the tube. The helical cut can have an axial length of at least 50 cm and be continuous along the axial length. DM US 45401381-1.080373.0657
