Based on http://www.thingiverse.com/thing:675419 I just widened the diffuser by 10mm to cover the entire flash. It is attached by sticking the clip through the front of the flash. Made to fit a Canon Rebel XT. Not sure what other brands/makes this might fit.

V2 I tapered the corners to make it easier to put the diffuser on from the front.

Print Settings

Printer:

Maker Select

Rafts:

Supports:

Yes

Resolution:

Infill:

20%