Abstract: An arm assembly for a disk drive having a read/write head and a servo head on the same Winchester arm assembly is described. To eliminate the possibility of crosstalk from the data head during the write mode, to the servo head, a mumetal shield is used to partially surround the servo head ferrite core and coil. The servo head is a composite structure having a non-conducting body and a thin ferrite core so that the magnetic core volume to be shielded is minimized. In addition, a conducting layer and a ferramic plate is interposed between the data and servo heads to further isolate these heads.