A breakdown spool comprising: a barrel having a longitudinal axis, a substantially annular winding surface surrounding the longitudinal axis, and an insertion section formed on at least one axial end (24, 36) of the barrel, the insertion section comprising an annular ring spaced from the axial end and projecting radially from the winding surface; at least one flange having a support surface, and a receiving channel formed within the support surface, the receiving channel for receiving the insertion section of the barrel, the receiving channel comprising a first portion for receipt of the axial end of the barrel, and a second portion for receiving the annular ring of the insertion section, the second portion recessed within the support surface such that the annular ring mates and aligns with the support surface on the flange upon insertion of the axial end of the barrel into the receiving channel; and a locking mechanism formed between the barrel and the flange, the locking mechanism including means for axially securing the insertion section of the barrel within the receiving channel of the flange: characterized in that the locking mechanism further comprises means for fixing the radial position of the barrel within the receiving channel relative to the flange, comprising a flexible locking tab on the flange and a corresponding engagement means comprising a notch formed within an extension foot portion on the axial end of the barrel, the barrel end being rotatable within the receiving channel to a position of engagement between the flexible tab and the engagement means. a barrel having a longitudinal axis, a substantially annular winding surface surrounding the longitudinal axis, and an insertion section formed on at least one axial end (24, 36) of the barrel, the insertion section comprising an annular ring spaced from the axial end and projecting radially from the winding surface; at least one flange having a support surface, and a receiving channel formed within the support surface, the receiving channel for receiving the insertion section of the barrel, the receiving channel comprising a first portion for receipt of the axial end of the barrel, and a second portion for receiving the annular ring of the insertion section, the second portion recessed within the support surface such that the annular ring mates and aligns with the support surface on the flange upon insertion of the axial end of the barrel into the receiving channel; and a locking mechanism formed between the barrel and the flange, the locking mechanism including means for axially securing the insertion section of the barrel within the receiving channel of the flange: characterized in that the locking mechanism further comprises means for fixing the radial position of the barrel within the receiving channel relative to the flange, comprising a flexible locking tab on the flange and a corresponding engagement means comprising a notch formed within an extension foot portion on the axial end of the barrel, the barrel end being rotatable within the receiving channel to a position of engagement between the flexible tab and the engagement means. characterized in that the locking mechanism further comprises means for fixing the radial position of the barrel within the receiving channel relative to the flange, comprising a flexible locking tab on the flange and a corresponding engagement means comprising a notch formed within an extension foot portion on the axial end of the barrel, the barrel end being rotatable within the receiving channel to a position of engagement between the flexible tab and the engagement means.