This contemporary and professional name is well suited to a hardware or security brand.
The name "stacksync" has nine characters and only two syllables. Two-syllable names are extremely rare and exceptionally valued. Examples of two popular syllable names include Apple, Pepsi and Buffer.
Stacksync.com is a .com domain. Dot com domains are the most prestigious top-level-domain in the world, used by famous websites like facebook.com. Once you own a .com, it will be much easier to rank for your own name in Google.