Technician a says that impact sockets have thicker walls than conventional sockets. Technician b says that impact sockets have a black oxide finish. Which technician is correct

Impact sockets are sockets used to cope with the vibration caused by the impact of the hammer on the anvil. Both technicians are right. It is true that impact sockets have thicker walls than conventional sockets, so technician A is right. But it is also true that impact sockets have a black oxide finish, so the technician B is also right.