A kit for the withdrawal of a blood vessel filter of the umbrella type formed from a bush (31) serving as a sleeve for retaining a number of flexible strands (32) that spread apart naturally and end in hooks (33) directed outwards so that they lock onto the wall of a vessel, comprisinga first so-called "external" catheter (1)a stem that can be inserted in the external catheter and has, at one of its ends, a number of flexible legs (18) that open out from the stem, spreading apart naturally and ending in hooks (20) directed inwards for grasping bush (31) of the filter as they close up again and preferably in addition a second catheter (11), of diameter such that it can be introduced into the external catheter (1).
