Despite initial concerns, I ordered this flap. I note that the back wall with flap can open better than without. This part looks good and is convenient. Even with one hand you have the open and close it quickly. The display is so well protected in pockets, the back also. To Halbarkeit I can not say anything - because I'll possibly do in a while a supplement.
The attachment of the flap is done by a battery cover which is used instead of the original. It is for this purpose from the original battery cover and push the battery cover flap and you're done.
The protection is good, the handling and the part also doing what it should - protect. More is not my opinion.
