Described is a needle assembly system (1) comprising a needle assembly (4) including a needle (4.1) and a needle support (4.2), and a cover (5) including a distal portion adapted to house at least a distal end of the needle (4.1) and a proximal portion adapted to house the needle support (4.2). The proximal portion includes a first portion (5.1) and a second portion. The first portion (5.1) has a first inner diameter substantially equal to an outer diameter of the needle support (4.2) and the second portion has a second inner diameter greater than the diameter of the needle support (4.2).
