a wound bobbin coil apparatus includes a coil form having a generally cylindrical surface having disposed at axial extremeties thereof generally circular side flanges . the coil form includes generally l - shaped cooperating locking member extending respectively from the generally circular side flanges , said locking members include means for locking engagement therebetween and include means for engaging a plurality of associated wires . the l - shaped locking members have at least one face thereof having a plurality of upstanding bosses disposed thereon in spaced relationship to allow entrance of termination wires therebetween .