TWC0008 is a crossflow charge air cooler for Western Star trucks.
The core measures 42" high by 25.125" wide, 2.5" deep. It has a 4" inlet at the left and a 4" outlet at the right. There is no integral oil cooler and no filler neck.
It replaces 6 OEM and aftermarket numbers, among them WES18206, WES18206N, 222384. Searching any one of them will find this part.
On charge air coolers the inlet and outlet positions and the boot diameters matter as much as the core. A cooler that fits the opening but presents its connections on the wrong side will not plumb up.