In
Germany, a rectangular board bearing the letter '
P' for "" ('whistle') is used as a whistle board. It may have either a black '
P' on a white background, or a white '
P' on a black background. Two boards, one above the other, means "whistle twice". Where an additional sign with two vertical stripes is mounted above the '
P' sign, that sign only applies to trains that are not stopping ahead (e.g. at a halt). ==Japan==