James the full part # is 573280. If you google the OPS 3280 you get the "marine and Drag" versions all with the same dimensions. Its a great pipe, very close to the CMB nitro pipe which is also a great pipe. It is well worth having both pipes since some engine setups will work better with one of the 2 pipes.
James, I didn't see that. However the Spec #s are both the same and the #85 sku number. The shipping weight off the drag is a little more .4 vs .5 . Maybe the drag pipe has a coating. I would e-mail them and ask for a explanation.