21mm Torque-Tight™ Lug Nut Indicators 21mm Torque-Tight™ loose lug nut indicators are used in some Class 1 and Class 2 truck applications. These smaller trucks are often tasked with making frequent stops throughout the workday. With Torque-Tight™ installed, drivers can quickly and visually check lug nuts during routine walkarounds, reducing the risk of wheel-off accidents. Why Torque-Tight™ Is Different Each Torque-Tight™ indicator is cut to a teardrop shape with 24 locking teeth that create an interference fit on standard hex nuts. Our indicators are designed to be more than twice as large as typical competitors, making them highly visible during inspections and walkarounds. Torque-Tight™ indicators are available in three standard colors—green, orange, and black—and custom colors are available with minimum orders. Key Features Colored pigment throughout for durability Lowest cost, highest quality in the industry 24 locking positions for easy placement Heavy-duty LDPE construction Injection molded for a precise fit 1/8" thickness for strength Resistant to extreme heat and cold Backed by a 2-year warranty Custom colors available on request Vehicles That Commonly Use 21mm Known applications for 21mm Torque-Tight™ indicators include: Ford F-450 (model year may vary) Ford F-550 (model year may vary)