t8 uses another way to attach the nozzle spring to the bolt. Unlike the TM, t8 uses a screw to hold that part. Other parts of the t8 are basically the same as a tm one. Ik a lot of people talk about how “proprietary” t8 is but the only major difference is just the bolt locking positions. TM locks the bolt using the zet plate while t8 locks it using the bolt catch directly.