This is the only style of bolt where the head is included in the length measurement, as it sits below the surface, the head contributes to the overall length. Made from 6AL-4V (Grade 5) Titanium and machined with fully cnc’d threads, this bolt is not only strong and lightweight but also offers great corrosion resistance. Socket Wrench Size M10 – 6MM hex key M12 – 8MM HEX KEY total LENGTH MEASURED FROM top of HEAD TO END OF THREADS ( TOTAL LENGTH!) 20 25 30 35 40 45 50 mm (CHOOSE FROM DROP DOWN MENU ABOVE) Please select quantity required from drop down menu PLEASE NOTE IF YOU SELECT ‘PACK QUANTITY – 1 , YOU WILL RECEIVE 1 BOLT ONLY ALL ITEMS SHIPPED SAME DAY IF ORDERED BEFORE 11AM MONDAY-FRIDAY * Image is for illustrative purposes only. I WILL POST ANY WHERE IN THE WORLD (EXCEPT RUSSIA) .