its almost a copy of the xray active diff. you will run alot lighter fluid in the front then usually. The xray guy run 1000 to 3000 in truggie. There is great right up of it on xrays sight that explains it. but i would still prefere the xray one comes with 2 different bevel plates to tune for high traction or low bumpy or loose traction.. But the losi one looks good with all the lightened outdrives and a great price...