Hose clamps come in a variety of sizes. Those for use on boats should be manufactured from 316 stainless steel or better.
Connectors, Hose Clamps
select hose clamp by its material
Hydraulic Hose Clamp: The Comprehensive Guide
WINL Stainless Steel Hose Clamps - 22 Pack Worm
Pro Tie 33106, SAE Size 80, Range 4-1/16 to 5-1/2 Inch, SS Turn
T-Bolt 3/4 inch Band Hose Clamps
Hose clamp - Wikipedia
What Are Hose Clamps and What Applications Are They Used For
OEMTOOLS® Medium Fuel Line Hose Clamp, 1/4-in/3/4-in, 44379