5 piece ACER Racing Titanium Lug Bolt set for Porsche 911 (996, 997, 991, 991.2 except GT3) Cayman, 718, Macan, Panamera and Porsche Boxster M14x1.5 thread 29mm length (will not work on cars equipped with spacers). Includes a key as shown. Porsche OEM Part number is 996 361 203 01 for the steel lug bolt and these are a direct replacement but in the highest grade titanium (Grade 5 6AL4V Titanium) Manufactured from aerospace grade 6AL4V Titanium, these titanium lug bolts will not corrode or rust and offer a significant weight savings over steel lug bolts while giving a very sporty and aggressive look. Titanium is 50% lighter than steel, yet considerably stronger. Titanium is also resistant to the constant heating and cooling cycles that destroy steel. Rolled threads for superior fatigue resistance.