The durability of the mask I guess as a really durable. No thin and quickly breakable material was used. The knob of the mask is always sideways.
Language is English - but that makes our guys do not mind, since most noise comes from the mask and not more than 1-2 sentences in English.
I can only recommend the product - but I find the MSRP quite high and had been looking forward that you are currently acquiring Amazon already 12 :)