For maximum durability in any situation Traxxas produced the Heavy Duty Suspension Arms for their legendary X-Maxx. This is a way to get even more brute strength out of your monste truck with these new heavy-duty suspension arms made from our composite material (specifically designed for high loads and hard landings with just the right amount of flex to resist breaking—even in cold weather).
Installation takes only a few minutes with no filing or modification required and come in six dynamic colors for full customization.
Source: www.traxxas.com