This is an envelope made of the first page of a calendar that shows two years: the Islamic year and the Gregorian year, solar-based. This is the kind of double calendars people have at home in Morocco. But, actually, the Islamic year is used only for religious festivities.
I sent it to Phillip (the USA) when 2016 started. I had almost forgotten it, but today some people is celebrating the Islamic New Year (1438), so this is a good day to publish it!