that is the combination of cards of the same value. they have been going out for six months. there are several experimental planes they were testing by the 1950s. your satisfaction is our primary concern. for further information in that regard, it's a matter of just checking that chart for that purpose. this is a truly one of a kind home! i prefer 7 over 8 myself, but i like both designs. now my advice for all you sad rhinos out there. those movements affect the observed period. the displays are clear and the options plenty, keeping you coming back for more. 