This contemporary and professional name is well suited to a hardware or security brand.
The name "stacksync" has nine characters and just two syllables. Two syllable names make popular global brands. Successful brands using two syllable names include FedEx, Subway and Google.
Stacksync.com is a .com domain. Dot com domains are the most popular, and the most desirable. Once secured, a .com all but guarantees no-one else can outrank you for your own name in the long run.