About to buy a turbo kit and wasn't 100% sure what I was getting into. The exhuast side says Garrett .63, but I can't find anything on the compressor side except for the letters "ITS" with an engraved sign that looks like some blades.

Can anyone give me more info on this please??

 

That literally could be anything. The company was called Innovative Turbo Systems (ITS), which is now called COMP turbo.

You can't just go by a turbine housing A/R. that is a tiny part of the equation of knowing what it will be. Remove the housings, measure the inducer and exducer wheels on each side, then find you're answer. Even pics won't help the most but will steer you in the right direction.