Coil Racks, Coil Bunks, and Coil Cradles: Don't Overlook the Little Pieces That Hold Back Big Weight

If you haul steel long enough, you're going to hear them called all kinds of names. Some drivers call them coil racks. Some call them coil bunks. Others call them coil cradles.

Whatever you call them, they all do the same job — and it's one of the most important jobs on the trailer. They're helping keep thousands of pounds of steel from rolling.

That's not something I take lightly. Under the coil rule, stopping that roll is required before a single chain goes on — I walk through the whole method in my guide to steel coil securement. This page is the buying side of it: what the rule actually requires, what's for sale right now, what each one is made of, and what it costs.

The ruleWhat a Coil Rack Does, and When the Coil Has to Be Cradled

A coil rack is a steel channel, usually about 33 inches long, with a raised stop at each end. You drop a hardwood timber into it, the timber is what touches the coil, and the rack keeps the timber from walking out from under the load. Set a pair of them under a coil and you've built a cradle. That's the whole job: hold the coil off the deck and stop it from rolling.

The federal rule is 49 CFR §393.120. It applies to metal coils that weigh 5,000 pounds or more, alone or grouped. Whether you need a cradle depends on which way the eye points:

• Eyes crosswise or eyes lengthwise: the coil can roll, so the rule requires a means to prevent rolling that holds the coil off the deck. If that means is wood, the wood has to be held by "coil bunks or similar devices." Nails alone don't count. This is where racks are mandatory.
• Eyes vertical (§393.120(b)): the coil sits flat and can't roll. The rule calls for diagonal and transverse tiedowns plus "blocking and bracing, friction mats or tiedowns" against forward movement. No cradle requirement, so racks are optional here.

Notice the regulation never says "coil rack." It says timbers, chocks, wedges, a cradle, and "coil bunks or similar devices." In the rule's language, the steel piece you buy is the bunk; the timber it holds is the chock. Everything in the table below is a bunk under that definition.

Plain wordsRack vs. Bunk vs. Timbers

Coil rack. The one-piece steel channel with end stops. Kinedyne describes its rack as "designed for use with hardwood timbers to secure metal coils," and US Cargo Control says the same about theirs: "used in conjunction with wood blocks to provide a place where a coil can be cradled." The rack doesn't touch the coil. It holds the wood that does. Standard-duty racks are 10-gauge steel; heavy-duty racks step up to 8-gauge, 5-gauge, or quarter-inch plate.

Coil bunk. In most catalogs this is the same product under a different name — Kinedyne's own product title is "Coil Chock or Coil Bunk." Some drivers use "bunk" for the heavier or wider versions, like the double-style rack that carries two timbers side by side, or a shop-built steel cradle. The regulation uses "coil bunks" for whatever holds the timbers in place, so any of these qualifies if it does that job.

Timbers. The wood. Usually 4x4 or 6x6 hardwood, often beveled on the side that meets the coil so the coil seats into it instead of sitting on a corner. Tarpstop sells 4x4 beveled coil lumber at $14.69 and 6x6 at $28.89 as of the day I checked. The wood carries the coil; the rack carries the wood. Wood nailed to the deck as the only thing holding it is prohibited by the rule quoted above.

What's for saleCoil Racks Compared: 11 Real Products

Every fact below comes from the seller's page linked in the Source column, fetched September 23, 2026. Where a page didn't list something, the cell says "Not listed." I did not fill in gaps from memory or from other brands. Two things stand out right away: no seller lists a coil-diameter range, and no manufacturer publishes a rated capacity for these racks. One seller says it outright: "Not rated. Positions the coil, does not restrain it." One retailer, MyTarp, gives "approximately 10,000 lbs" per rack as a rough figure on its Kinedyne listing. Treat that as a retailer's note, not a manufacturer rating.

Notes: the US Cargo Control heavy-duty rack and the Tarpstop double-style rack list identical dimensions (38.5" × 3.77") and near-identical weights; I'm reporting what each page says, not claiming they're the same part. Tarpstop also lists a "Heavy Duty Style Coil Rack" at $12.99 (32.5" long, 7 lb) that was backordered on the day I checked, so I left it out. Mytee Products' listings couldn't be read by the tool I used, so they're not in the table either.

ChoosingHow to Pick by Coil Size and Weight

Start from what the sellers don't tell you. None of these racks publish a coil-diameter range or a rated capacity, so you can't pick one off a spec sheet the way you'd pick a chain by its working load limit. What you can compare is steel thickness, rack length, inside length, and what size timber the rack is built for. The rack's job under the rule is to keep the timber from coming loose; the tiedowns through the eye are what actually restrain the coil. Size the rack to the timber and the timber to the coil, and let the chains do the holding.

Standard coils: 10-gauge, 33-inch, 4x4 timbers. The 33-inch 10-gauge rack is the standard-duty class across every brand in the table — Kinedyne 8656, Ancra 49344-10, US Cargo Control's light-duty rack, Cargo Control Center, and Carolina Tarps all land there, between about $10 and $18 apiece. The US Cargo Control unit lists a 27.7-inch inside length, which tells you how long the timber can be. For the big, heavy coils, step up to thicker plate: Kinedyne's 8-gauge 80044, the quarter-inch Ancra 49344-12 and US Cargo Control HDCOIL2, or Tarpstop's over-sized rack, which is the only one in the table that says what lumber it's built for (6-inch) and how much room there is between the stops (34 inches). Those weigh three to four times as much and cost two to seven times as much; that's what you're paying for.

How many, and what to check. Kinedyne's retailer listing says three racks minimum per coil and four recommended; my own rule is to carry at least sixteen on the trailer, because a load of small coils will eat that many fast. Before every load, look each rack over for cracks, bent stops, and rust-through, and make sure the timber can't ride up out of it — that "must not be capable of becoming unintentionally unfastened or loose" line is the part of the rule an inspector reads back to you. A rack that lets the timber walk is worse than no rack, because it looks compliant until the first hard brake.

Once the racks are set and the coil is stopped from rolling, the rest of the job is the tie-downs and the cover. The chain that goes through the eye is the subject of my Grade 70 chain guide; if you're wondering why a coil never gets ratchet straps where a lumber bundle does, that's in chains vs. straps. The cover is a steel tarp, not a lumber tarp, and a coil on a rack sits higher than you think, so measure the height and let a truck GPS route you before you roll.