Na several different backs, shells and cups I am now but ended up with Samsung only. The brown envelope will also sit on a blue cell phone, and gives the whole a very noble, "serious" touch. Unfortunately, the back is similar to the original somewhat susceptible to scratching the phone itself - so you can see, especially against light as a few locations, if the mobile phone is a couple of times slipped on a table back and forth. I expect to have the shell every few years change me, but that is ok. ;)
Calls works perfectly the way also closed Flipcover if you have accepted the call first.