TPI Wheel Bolts (10 pcs), Conical Seat, 17mm Hex, M14×1.25, 45mm, Black

TPI locking wheel bolts are used to securely fasten the wheels of your car. They are made of high-grade chrome-vanadium or chrome-molybdenum steel that has undergone a heat-hardening process to ensure consistent hardness and strength. The bolts have an M14 × 1.25 thread with a length of 45mm and a 60° conical seating surface. The surface finish protects the bolts from corrosion. A 17mm hexagon key is used for installation.

High-Grade Steel and Heat Treatment

The wheel bolts are based on high-grade steel of the ASTM 4140 or SCM 440 specification, also known as chrome-molybdenum or chrome-vanadium steel. The material undergoes a heat-hardening process, which gives it consistent hardness and strength throughout its entire volume. This allows the bolts to reliably withstand the high stresses that occur during tightening and while driving.

Corrosion Protection and Testing

The surface finish protects the bolts from external influences and extends their service life. Depending on the variant, a layer of zinc is applied, or a combination of triple nickel plating and chrome plating. The layers create a barrier that provides high resistance to weathering, moisture and road salt. The reliability of the protection is verified by a salt spray test. In addition, the bolts also undergo a tensile test, which confirms their mechanical integrity and ability to withstand the prescribed load without deformation.