A needle protector assembly (10) comprising a needle defining an axial direction and a protective cover (20) for the needle, wherein the needle is attached to a needle connector which is provided with fins (16) on sides opposites thereof and which can be moved with respect to the protective cover (20) between a distal position in which at least one tip of the needle projects from the protective cover (20), and a proximal position in which the needle it is received entirely in the protective cover (20), in which the protective cover (20) comprises first and second parts (26, 28) that together form an elongated housing along which the needle connector can move between the distal and proximal positions, in which the first and second parts (26, 28) define elongated grooves (46) on opposite sides of the housing through which the fins (16) project, and in which the first and second (26, 28) are connected and each other by means of a flexible hinge in the region of a first axial end (22) of the housing and by means of a latching mechanism in the region of a second axial end (24) of the housing, in which a mechanism is provided locking mechanism, which is adapted to fix the needle connector in the proximal position, wherein the locking mechanism comprises a pair of first and second locking means which engage with each other when the needle connector is in the proximal position , wherein the first locking means is provided in the needle connector and the second locking means is provided in the protective cover (20), characterized in that the first locking means is formed so that a radial dimension can be reduced of the first blocking means against a restoring force.Un conjunto protector (10) de aguja que comprende una aguja que define una dirección axial y una cubierta protectora (20) para la aguja, en el que la aguja está fijada a un conector de aguja que está dotado de aletas (16) en lados opuestos del mismo y que puede ser movida con respecto a la cubierta protectora (20)
