This replacement boat trailer guide on pole is manufactured out of 1 1/2" square aluminum tubing with 1/8" wall thickness. It measures 46" tall and has a 24.5" long leg for easy width adjustment to fit the sides of your boat as is goes onto your trailer. It has an aluminum welded tab to serve as a stop for your pvc. This guide pole is designed to have 2" pvc slide over top of it. The pvc sleeves are available separately. The guide poles typically attach via u-bolts to the main I-beam frame or into a cross member. Mounting hardware is sold separately. This is for (1) single replacement guide pole. This Guide Pole is bent at 90 Degrees for perfect alignment with the side rail of your boat. If you are mounting this Aluminum Guide Post to an aluminum I Beam trailer frame, the simplest way is by using (2) Stainless Steel Square Ubolt 3/8 inch x1 9/16 inch x 2 1/2 inch to drill directly into the I-Beam. The combination of Aluminum against aluminum with stainless steel will be the longest lasting guide pole system possible. If you are wanting to mount this guide post to a Square tubing or C-Channel shaped frame, you will be needing a 1 1/2 inch Galvanized Boat Trailer Hat Bracket with the correct height and width of 3/8" diameter Boat Trailer U-Bolts that will fix around your frame. It is also not uncommon to have to get U-Bolts that are wider than or longer than your frame. The important part is that the tightening of the U-Bolts will prevent your guide poles from moving.