T-H Marine Stainless Worm Gear Hose Clamps 3/8-7/8" 2pk

Every boat runs on hose. Livewell fill lines, aerator plumbing, bilge pump discharge, washdown feeds, scupper drains. All of it has to stay sealed, and the humble hose clamp is what keeps those connections from weeping or blowing off. This T-H Marine set gives you two stainless steel worm gear clamps with a 3/8 to 7/8 inch clamping range, which is the sweet spot for the small-diameter hose you find all over a center console, bass boat, or pontoon.

A worm gear clamp is the classic design you already know. A slotted stainless band wraps the hose, and a captive screw threads through those slots. Turn the screw and the band draws down evenly around the fitting. Back it off and the band opens up. It's simple, it's adjustable, and it holds. You don't need a special tool, just a flat screwdriver or a nut driver that fits the screw head, and you can snug it by hand in a tight bilge without fighting it.

The 3/8 to 7/8 inch range covers a lot of common marine plumbing. Think 1/2 inch inside-diameter aerator and livewell line, small bilge hose, baitwell overflow, scupper tubing, and the vent and feed lines on a lot of deck hardware. Measure the outside diameter of your hose where it sits over the barb, and if that number lands inside 3/8 to 7/8 of an inch, these clamps will close down on it. For anything bigger, you'll want a wider-range clamp.

Not sure what you've got? Pull one existing clamp and read the range stamped on the band, or wrap a tape around the hose and fitting and divide by pi to get the diameter. Most small boat plumbing lands right in this window, which is why a 3/8 to 7/8 inch clamp is one of the handiest sizes to keep aboard.

Here's where material matters. A boat is a brutal place for metal. Salt spray, bilge water, humidity, and the occasional dunk all gang up on cheap plated clamps, and a rusted clamp is a clamp that's about to fail. T-H Marine built these with a stainless steel band so they stand up to that abuse far longer than a zinc-plated clamp from the auto parts aisle. Rust streaks on your transom or down a livewell wall usually trace back to the wrong hardware. Stainless keeps things clean.

Installing them is quick. Slide the clamp over the hose before you push the hose onto the barb, then position it just past the barb's ramped end so the band sits over the solid part of the fitting. Snug the screw until the hose bites into the barb, but don't go gorilla on it. Overtightening can cut into softer hose or strip the band slots. A good clamp is tight enough that the hose won't twist off by hand, no more. Leave the screw head where you can reach it later, because you'll be back in there eventually.

You get two clamps in the set, which is handy. Most hose connections want a clamp on each end, so a pair does one full run, or you keep the second as a spare in the parts box. And you should keep spares. Clamps are the kind of small part you always need at the worst possible moment, usually at the ramp on a Saturday morning. Whether you're re-plumbing a livewell, chasing a bilge leak, or just upgrading tired hardware during spring commissioning, these are the clamps that quietly do the job.

One honest note. Worm gear clamps like these are made for low-pressure plumbing, the aerator, bilge, washdown, and drain hose that makes up most of a boat's wet side. They're not the right choice for high-pressure fuel injection or hydraulic lines, where your engine maker and ABYC guidelines call for specific fuel-rated clamps. Use the right clamp for the job, and for everything else on the boat's plumbing, this set has you covered.