Combination of the words "turbo" and "grade" makes for a memorable domain name.
The word "TurboGrade" contains 10 characters and three syllables. Established brands using three syllable names include Vodafone, Santander and McDonald's.
Turbograde.com is a .com domain. Dot com is the most desirable domain extension. Once secured, a .com all but guarantees no-one else can outrank you for your own name in the long run.