Chain - High Test 40/43

What Is High Test 40/43 Chain?

High Test chain — commonly designated Grade 40, Grade 43, or simply "HT" — is the modern standard for marine anchoring and ground tackle. Grade 40/43 chain is made from high-tensile carbon steel and is widely used across the boating community for its exceptional strength-to-weight ratio compared to older chain types. As advances in metallurgy brought stronger, lighter options to market, High Test 40/43 chain largely replaced heavier legacy chain as the go-to choice for recreational and cruising vessels.

Why High Test Chain Matters for Anchoring

The critical job of an anchor rode is to transfer holding load from your anchor to your boat — and the chain section of that rode plays a defining role. The weight of the chain causes it to sag and form a catenary curve, pulling the load at the seabed nearly parallel to the bottom. This horizontal pull helps the anchor set firmly and hold in a wide range of conditions.

Grade 43 High Test chain delivers a working load limit approximately twice that of BBB or proof coil chain of comparable size, allowing boaters to use a lighter, smaller-diameter chain while maintaining — or exceeding — the same holding security. That weight savings at the bow can meaningfully improve a vessel's trim, reduce pitching in a seaway, and allow for carrying a longer rode without overloading the chain locker.

The short ISO link geometry used in Grade 40/43 chain is equally important. Shorter links make the chain more flexible, less prone to tangling in the chain locker, and compatible with the wildcat on most windlass models — a critical consideration for any boat equipped with a powered anchor windlass.

Key Features to Look For

• Hot-dip galvanizing: The most durable corrosion-resistant finish for saltwater use. Shot-peening the chain before galvanizing further improves the coating's bond and longevity.
• ISO short-link design: Calibrated to fit most windlass wildcats designated for "HT" chain. Always verify compatibility with your windlass manufacturer before purchasing.
• Domestic manufacturing: U.S.-made chain is subject to consistent quality controls and traceable material standards, an important consideration when your rode is the last line between your boat and the seafloor.
• Size selection: Common sizes for recreational use are 5/16", 3/8", and 1/2". The right size depends on your vessel's displacement, typical anchoring conditions, and windlass rating.
• Factory proof testing: Quality chain is tested to a multiple of its working load limit at the factory, giving each link a documented margin of safety before it ever reaches your boat.

Top Brands in High Test 40/43 Chain

Acco Peerless Chain is the most recognized name in American-made marine anchor chain. Established in 1901 and now operating under the Peerless Industrial Group, the brand has spent over a century building a reputation for high-strength chains used in marine, industrial, and agricultural applications. Their Grade 43 High Test ISO chain is manufactured from high-carbon steel, hot-dip galvanized for corrosion resistance, and factory-tested to stringent performance standards — making it a trusted foundation for any serious anchoring system.