36720 - Printed circuit boards
3672012 - - Printed-circuit (Wiring) boards, Single-sided glass
3672014 - - Printed-circuit (Wiring) boards, Double-sided glass
3672016 - - Printed-circuit (Wiring) boards, Multilayer glass
3672018 - - Printed-circuit (Wiring) boards, Paper/mat/composite
3672022 - - Printed-circuit (Wiring) boards, Flexible circuit
3672024 - - Printed-circuit (Wiring) boards, other Rigid laminates
3672026 - - Receipts for Contract work on printed circuit boards
3672XX0 - - Printed circuit (Wiring) boards
3672XX2 - - Printed circuit boards (Miscellaneous : Speciality )