The Aries Round Nerf Bars part # AA200112 have a shipping weight of 48 lbs and shipping dimensions of 69" long x 16" wide x 4" tall. view full answer...
There are a few shanks that are specifically designed to be used in the rise or drop position only, but it will be clearly stated in the product description.
The vast majority of the weight distribution shanks, like the # RP54970 you mentioned can be used in either the rise or drop orientation.
The procedure for determining the necessary rise or drop needed is much like that used for a ballmount, see the linked FAQ article. view full answer...