DD MK18 RIS II upper build ?

[Lawdog-1]

Do I really need the DD Armorers wrench or will Smith Enterprize Armorer wrench or DPMS Armorers from Brownells get the Job done?

[SPDGG]

You will need the proprietary Daniel Defense Lite Barrel Nut Wrench

AR15 Lite Rail Barrel Nut Wrench
http://www.danieldefense.com/?page=shop/detail&product_id=62