Originally Posted by Freddie B
The shortened shroud would be nice sometimes, and maybe even cut all the way back to the stator vanes if you really wanted to save weight, like the GP 30mm fan does. However a quick cut with a razor saw, a sanding block, and the shroud is whatever length you want.
The Bellmouthed Shrouds would have you cutting off the bellmouth. Also, since the motor support has a lip on this version, the motor can only be loaded from the back and its very hard for human sized fingers to install the fan way down in the hole.
Earlier versions didn't have this lip and the motor could be pushed forward, fan installed and motor pushed back. I like the lip, because it provides a positive forward stop for the motor, but installing the fan on the motor is tough.