Its the factory tentioner just moved to other side of engine, custom bracket holds it in place.
You have to use the Magnum balancer and flex if you have a 5.9 or if you want to run factory injection.
The 318 and 5.2 can use same balancer, 360 LA is different as is 5.9 magnum and 360 wont work on 5.9.
FYI Only 2002-2003 5.9's have a pulley/balancer cast together, all the rest are separate with the exception of a few late 2001 5.9 Durangos and Dakotas. PRW makes a better balancer that works on all LA as well as all Magnum V8's....comes with 3 balance weights that screw on for late 340, LA 360 and 5.9 Magnum