Titanium Button Head M4 - 0.70 X 40MM. Grip Length = 15MM. Thread Length = 25MM. The drive on this bolt is a 2.5M Allen/Hex Key. Head Diameter is 7.5mm. The heads have been forged and the threads have been rolled for better fatigue resistance. Made from Aircraft grade material that has a Minimum UTS of 140Ksi (925Mpa).