Product Details The all newChinook Sailing 1-Bolt Pro Flex Mast Base Euro-Pin EXfeatures all of the advantages of a tendon base with the added features of a mechanical base. ***Specifically designed for Foiling (Not recommended for Bump and Jump, Slalom or Formula Racing. If used as such warranty is null and void*** Uses a shorter Proflex Chinook Tendon for easy serviceability. Free moving Mechanical hinge provides ease of attachment for larger or wider Foil boards, Formula, & Long boards etc. Foil Boards eliminates likely hood to flip over during attachment or waterstarting. Mechanical hinge eliminates an estimated 75-80% of fatigue which occurs due to constant bending of the Tendon. Made in cast 316 Stainless steel like our other Euro-pin bases so it will be extremely durable & have the distinctive look of polished steel. Available in 1-Bolt, 2-Bolt Euro-Pin Base & US Base Cup versions!