Can I add THC to my machine later? June 21, 2021 21:50 Updated You do not need to include THC in your initial purchase, it can always be added to your machine later on. Related articles Can I use THC on the original CrossFire machine? What is the difference between Torch Height Control (THC) and Initial Height Sensing (IHS)? THC Function - Internal Wiring THC Function - CNC Port Wiring XL Kit Lower Rails Differentiation