If you do a lot of trailering the black ones to leave marks, I had the plastic blue ones with the white inner that worked well but eventually cracked and fell off. The best ones I have found are these orangeish colored ones, the are flexible like the black rubber ones and one solid piece like the black rubber ones but they do not mark the hull. I got them from a trailer place in Florida , they definitely weren't cheap to replace on the entire trailer but hopefully they won't need to be done again.i have had them one the trailer for 2 years but the amount of use they have seen is more than most people do in 10 years.
