Patent ID: 7412768

Claim:
A device comprising: a spool for a trimmer head; a spool turning member for turning said spool within the trimmer head, said spool turning member including at least a drive portion having a noncircular shape, and a knob, which is a portion of the spool turning member that is adapted to be turned by a user; and the spool having at least a top having a noncircular socket that is contoured for releasably attaching the knob by at least mating with the noncircular shape of the drive portion; a bottom having a noncircular socket that is contoured for releasably attaching the knob by at least mating with the noncircular shape of the drive portion; at least one abutment for releasably engaging and contacting a mechanical bias via the top of the spool and via the bottom of the spool; a core, the core having at least sides for winding trimmer line around, a core top, which forms a part of the top of the spool, and a core bottom, which forms a part of the bottom of the spool; the abutment being located in the core; wherein when the spool is not inverted, the mechanical bias is received and supported by the at least one abutment via the top of the spool, and the knob is releasably attached to the bottom of the spool, and when the spool is inverted, the mechanical bias is received and supported by the at least one abutment via the bottom of the spool, and the knob is releasably attached to the top of the spool.