From Tekno RC:
By lowering the hinge pin location compared to the stock rear hubs (TKR5545), we have raised the rear roll center in just the right place. Use these hubs to increase on power traction and stability while decreasing body roll. All of this with improved rotation into a corner and no compromise in on-power steering. To reduce wear and increase part lifespan, they are molded from durable nylon and are for use on the SCT410.3 and EB48SL vehicles. No setup changes are necessary when switching from the stock SCT410.3 rear hubs (TKR5545) to run the new HRC rear hubs (TKR5545B).