Co2 tubing are made of silicone, which is soft and stretchable like a rubber band. (Regular airline hoses are NOT stretchable like rubber bands!) I have a Planted FW tank and I deal with CO2 a lot. the majority of silicone tubing are colored (black, blue, green) that's why I think your tubing is 'legit'.
A quick Google search also confirmed that yours is indeed Silicone.