Originally Posted By: Iowegian
Purolator Boss
Also, Amsoil = Royal Purple.
Royal Purple makes Amsoil filters and they are identical accept for color.
Royal Purple does not manufacture oil filters, Champion Labs makes both filters.
The AMSOIL EaO existed long, LONG before the Royal Purple filter did. AMSOIL was probably the first company to have manufactured for Passenger Car applications a synthetic glass media filter, which utilized Donaldson's proprietary synthetic glass filtration technology and was assembled by a traditional filter manufacturer.