These are NOT cheap automotive-style band clamps They are a 100% stainless steel band, clamp, and screw. These clamps are designed to give years of trouble-free service. Don't trust anything but the best for your boat.
T-bolt clamps are the very best clamp money can buy. They are virtually impervious to harsh elements and are super-strong. If you want the best, use T-bolt clamps. Available in many sizes from 1" to 6"