At these prices, the door is open for a permanent substitution of copper.

Supply isn't going up as much as demand so the prices of metal, especially that of copper and zinc, are going up.

As long as natural rubber prices do not outstrip synthetic rubber prices by a large margin, substitution with synthetic rubber by tire manufacturers isn't expected to be very significant.

I have an open-door policy.

An open door invites callers.

The door is now open for discussion,