In the early 70's, Eric Giese was working for NASA. Space suits have cooling, heating and electric lines running throughout the suit and a major problem was the lines getting kinked at the knees and ankles when the astronauts walked. The solution was articulaing hinges that allowed for more flex. In the late 70's, Eric applied this concept to skiing and the first 3-piece ski boot was born. His goal was to enable the boot to flex without bulging/distorting in the lower shell. This was the largest single problem of the day, especially since ski boots at the time had no ankle hinge. The ankle is of course a critical area of fit where any distortion would immediately causes a loss of control. This is how the ribs of the original Raichle flexon tongue were conceived. The revolution in 3 piece boot design started here, and will now continue from here ... For the good of skiing.