Polyform HTM-4 Center Tube Boat Fender 13.5" x 34.8" Black

The Polyform U.S. HTM-4 is a big center tube fender built for the boats that need real stand-off, cruisers and motor yachts in the 40 to 50 foot range. At 13.5 inches across and 34.8 inches long, it puts a lot of cushion between your hull and the dock, the piling, or another boat. Black, ribbed, and made from heavy marine-grade PVC, it's the kind of fender you rig once and stop thinking about.

HTM stands for hole through middle, and that's exactly how this one works. A molded center tube runs the full length of the fender so you thread your line straight through the core instead of tying off at one end. Hang it vertically off a cleat or a rail and it sits flat against the hull, right where you want the contact. Because the load runs through the center of the fender and not off a single tab, it stays put in a chop and doesn't roll up out of position when a wake rolls through the slip.

The ribs aren't just for looks. Those molded-in ridges add wall strength and help the fender grip against the hull and the dock face so it holds its spot. Polyform builds these with even wall thickness and reinforced tube ends, so the two spots that usually fail first on a cheap fender, the seams and the rope holes, are the parts they beefed up. It's an inflatable fender, so it ships with an air adapter and you set the firmness yourself with a standard pump.

Run a 5/8 inch line or larger through the center tube. Anything thinner tends to bind on the ribbed interior and makes adjusting the height a fight. A quick tip from folks who rig these all the time: soak the rope in fresh water before you thread it through the first time. The wet line slides through the tube with a lot less friction and saves you skinned knuckles.

This is the fender you reach for when you're coming into a fixed dock on a 45 foot trawler, rafting up against another boat for the weekend, or laying up against a piling where a smaller fender would just disappear. The 13.5 inch diameter gives you enough stand-off to keep rub rails and gelcoat clear of a rough bulkhead. On boats with narrow side decks or fine toerails, that same width can be more fender than you need, so check your freeboard and rail height before you commit to this size. For most 40 to 50 foot hulls it's right in the sweet spot.

A bare black fender will leave marks on a white hull if it works back and forth against the gelcoat all season, so a lot of owners slip a fabric fender cover over it. The cover takes the scuff and washes clean, and the fender underneath stays looking new. It's a small add that pays off on a topsides you care about.

Take care of it and it'll last. The most common way these wear out is UV, not impact. If you keep your boat in strong year-round sun, ease off on the inflation pressure and get it out of direct sunlight when you can, because a fender left rock-hard and baking will stress the seams and the end caps over time. Don't over-inflate. Firm is good, drum-tight is asking for a leak. Rinse the salt off now and then and it'll hold its finish for years.

Sold as a single fender. If you're fendering a 40 to 50 foot boat properly you'll want several down each side, so plan your quantity for the length of dock contact you actually need.