A "one letter" gTLD which consists of actually 10 characters. Only possible with the new gTLDs!
With the new gTLDs everyone's counting the keyword after the dot and seeing the domain as a whole for a domain to make sense (with the exception of certain gTLDs such as .xyz, since after the dot has zero meaning there). But when it comes to "one letter" gTLD domains a lot of gTLD registrants suddenly ignore what is after the dot, as if the extra characters suddenly don't make the domain longer anymore. I never considered domains such as x.photography (12 characters!), b.accountant (11 characters), t.technology (11 characters),... "one letter" domains, but that's just me.
Personally I would skip these 2 and use the $280 you save on yearly renewals to buy a decent ccTLD or .com. I'm sure you can buy one or two decent/good domains shorter than 10 characters for that money, and probably with a <$10 renewal rate.