When RAM DS was updated to DT, the Atrax 17 was no longer compatible due to the upgraded 6 lug bolt pattern and larger brake system.  RAM DT customers immediately began requesting a Bawarrion solution.  Bawarrion responded and the Atrax 18 was born, just like the Atrax 17 the 18 is approved by TUV Sud / Germany for your RAM DT and TRX with up to a 35x12.50 tire.