These valve locks feature a lash cap as part of the lock. Because of this design, lash cap or lock failure is virtually non-existent, even in the most extreme conditions including nitro applications. These valve locks are precision cut from tool steel, to give the highest in quality and reliability. The unique ?S? cut design gives a more positive lock along with greater strength. Sold in pairs (8 cyl. engines require 16 total). Note: Due to machining process these Lash/Locks must be kept as pairs, valves are not interchangeable.