[diamond_SEA]

Easily said:

companies like ICS, CA, JG, etc are all built off the TM base (TM being the oldest manufacturer of the modern AEG). They all offer some differences (some have metal bodies, others are cheaper), but they all are basically the same: they are airsoft guns.

A PTW on the other hand, is not exactly an "airsoft gun" and rather more of a simulation device. PTWs are built with the highest quality, strong, and to exact dimentions. PTWs are known to accept parts like upper recievers from real m4 models.

So, in short, an ICS is not a Systema, besides the obvious manufacturer difference, is that ICS is an airsoft gun manufacturer, and Systema is a simulation weapons manufacturer. I know they do the same thing in the end, but there is a huge difference.