My tank was attached just like stated above from the factory, neoprene strips as barriers to the hull bottom, and under metal straps over the top as tie downs....no foam or cushioning, ...lasted over 20 years since new, and going back in service after some pit repairs.....one thing I did notice is some more pitting under the neoprene strips, than the surrounding areas...I just chalked it up to "air circulation is your friend" when it comes to alum tanks.....