Parts in ITrack represent parts pulled from a vehicle during teardown, aftermarket parts you purchase directly, or replenishable inventory. Parts can either be sold to a customer on a Sales Order, or consumed on Work Orders. If you pull a part from a vehicle, it is recommended that you enter that part on the vehicle teardown screen. Parts you acquire directly from a vendor can be entered on the Parts screen.
Read more about entering parts from a Vehicle Teardown.