Until now, all Stanley-type bench plane irons were bedded at 45°, or Common Pitch. But the famous English Smoothers like Norris are usually 50° (York Pitch) or 55° (Middle Pitch). The higher pitches make smoothing difficult wood easier. Our unique High Angle Frogs quickly convert our No. 4 and No. 4½ Smoother to York or Middle Pitch. These frogs will also fit our other planes with 2" (5.08cm) or 2-3/8" (6cm) blades. Will not fit other makes of planes. May be ordered extra or installed in the tool.