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The strongest and most consistent lug nut on the market for doing the single most important thing a lug nut should do:


CREATE STUD TENSION (also known as stud preload, or clamping force). 

Manufactured in the USA from hardened USA alloy steel, the unique floating collar design removes aluminum (wheel nut seat) from the underhead friction equation when turning/tightening the lug nut (aluminum galls very easily. Why is that bad?).

By eliminating the detrimental effect of aluminum galling on stud preload (see chart in pic gallery), the Core4 Flugs can generate optimal stud tension/preload from the 1st time you tighten them when new, to the 30th+ time, without lubrication anywhere on the threads or nut seat. No other lug nut achieves this, regardless of coating type. Long term tension consistency = long term safety and long stud life.

The Core4 Flug design also reduces static bending strain on the studs from manufacturing tolerance stack up in the wheel hub and tapered nut seats of the wheel. If the tapered seats of the wheel aren't perfectly concentric and aligned with the wheel hub stud/bolt circle, 1 or more wheel studs are always subjected to static bending strain once tightened. This is a significant reason why there aren't tapered seat wheels on larger bolt circle and higher count bolt/stud heavy vehicle applications. 

Core4 "FLug" Nut (Floating Collar "Wobble" Lug Nut)

    • Unparalleled torque-tension performance and consistency over the lifetime of the lug nut

    • More stud tension consistency = minimized early fatigue failure of wheel studs

    • USA alloy steel, and manufactured in the USA

    • 160,000+ psi tensile strength (35+ Rc hardness) for extra durability, longevity, and proper match with class 12.9 wheel studs (OEM is 10.9) 

    • Oversized thread to facilitate faster tightening and minimize galling

    • Large lead-in beveled edge for cross thread proof quick tightening

    • MIL-SPEC high performance, high visibility cadmium plating 

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