12 point chromoly head nuts. Increased torque to 65 foot pounds. No drilling or tapping required, meaning cost wise this kit is about the same as other kits that seem less expensive. This is a bolt on kit with no machining required. The item "Honda TRX400EX TRX 400EX KMS ARP Stronger Heavy Duty Cylinder Head Studs Kit" is in sale since Tuesday, March 31, 2015.This item is in the category "eBay Motors\Parts & Accessories\ATV, Side-by-Side & UTV Parts & Accessories\Engines & Components". The seller is "azquadparts" and is located in Gilbert, Arizona. This item can be shipped worldwide.