Abstract: The slitter includes a handle section having a handle member and an arcuate section joined thereto, a knife blade, a clamp member and interfitting parts for mounting the clamp member to the handle members for limited vertical movement between catheter clamping and release positions, each of the arcuate section and the clamp member having vertically opposite facing surfaces for clampingly engaging opposite surface portions of any one of a number of different outer diameter catheters. The arcuate section has a nose portion for entering between the clamped catheter and the introducer when the introducer is to be removed from the catheter without being moved over the proximal terminal end of the catheter. The knife blade is located radially outwardly of the arcuate section surface that abuts against the clamped catheter, extends radially outwardly of the nose and is located rearwardly of the forwardmost part of the nose.