The allow you to see the location of your trailer when it's under water. The 2" PVC tubes make it easy to see your trailer's position when backing down the ramp.•Mounting hardware included•Sold in pairs•Adjusts out to 19" each side•Fits frames up to 3" W x 4-1/4" H•1-1/2" square, 16 gauge pre-galvanized steel uprights•39" high•2-3/8" diameter white PVC posts. •Stands 60" above the trailer frame with white post caps. •Made in the USA•Durable pre-galvanized steel Fits frame rails 3â wide x 4-1/4â tall Made in USA Durable pre-galvanized steel is corrosion and rust resistant | Overton s 60" Post Guide-On with Unlighted Posts in White Made in USA