A set for peripheral nerve blocking, including a rigid cannula, an outer catheter sleeve which can be slid over the cannula, where the distal tip of the cannula protrudes over the distal end of the catheter sleeve, an inner catheter which can be inserted through the catheter sleeve after removal of the cannulate from the catheter sleeve and which has an outlet opening at the distal end, and a first connector piece at the proximal end of the catheter sleeve, where the inner catheter has a second connector piece complementary to the first connector piece, and the inner catheter can be fixed in an axial position by connecting the first connector piece and the second connector piece in the catheter sleeve, in which axial position the distal end of the inner catheter protrudes from the distal end of the catheter sleeve with a pre-defined length which has the outlet opening.
