I recently painted the rear 2/3's of my hull bottom with a product called Slip Plate #1. Also applied it to the stomp grate. Did this for two reasons to make the boat slide off and on the trailer easier and to perhaps help it to skim over shallow gravel bars. Finally got the boat in the water yesterday and the first half of my expectations were met. The boat launched in far less water and I had to back off when putting it back on the trailer or I certainly would have over shot. Left about a foot for the winch to do and that too was much easier. This stuff is used in farm and construction equipment to make things slide in and out easier. I bought 6 spray cans for about $50 at Graingers and did the job with three so I will have plenty left for touch up.