Ring Spanner Wrench 5.5mm-41mm Metric Ring Deep Double Offset High-carbon steel

Measure across the flats of the bolt head or nut with a caliper or ruler — this is the wrench size you need. Each variant lists a size range (e.g., 10mm–12mm), meaning the wrench fits both the smaller and larger end. If your bolt measures 11mm across the flats, select the 10mm–12mm variant. When in doubt, size down rather than up to avoid slippage.

A double offset ring wrench has its ring head angled away from the handle plane — typically by 15° — on both the vertical and horizontal axis. This lifts your hand and knuckles above the work surface when turning, which is critical when working in tight engine bays, under vehicles, or on machinery where a flat wrench would scrape your hand on surrounding components.

High-carbon steel offers good hardness and resistance to deformation, making it suitable for most automotive and general mechanical fastening tasks. For extreme torque applications (e.g., large suspension bolts or industrial flanges), always use a torque wrench to avoid exceeding the tool's rated capacity. If you need to confirm the specific tensile rating for a particular size, contact us.

The polished finish provides a degree of surface corrosion resistance, but no bare steel tool is fully rustproof in persistently damp conditions. We recommend wiping the wrench with a light machine oil after use and storing it in a dry toolbox or roll. Avoid leaving it in contact with wet surfaces for extended periods.

These wrenches are sized in metric (mm) and are designed for metric hex fasteners. While some metric sizes are close to SAE equivalents (e.g., 13mm is near 1/2"), using a metric wrench on an imperial fastener — or vice versa — risks rounding the fastener corners. For SAE fasteners, use a wrench sized in inches.

Choose 1 piece if you need a specific size for a single repair job. Choose 2 pieces if you frequently work on tasks requiring the same size at two points simultaneously (e.g., bolt-and-nut tightening without a second person). Choose 5 pieces if you're stocking a workshop, running a small repair business, or want backup tools for a size you use regularly — the per-unit cost is lower at higher quantities.

A deep ring profile means the ring opening has greater depth (height) than a standard ring wrench, allowing it to seat fully on fasteners that sit slightly proud of a surface or have a longer hex section. This is particularly useful on socket-head cap screws, thick flange nuts, and fasteners with extended hex profiles common in machinery and automotive suspension systems.