Many factors are to be considered to ensure selecting the correct threadlocker for your application.   Threadlockers are available in low strength ( purple ), medium strength ( blue ), and high strength ( red ).  The blue threadlocker is typically the most common threadlocker sold today.   A blue threadlocker is to be used when on bolts up to 3/4″ in diameter.  Bolts applied with medium strength blue threadlockers can removed with hand tools and can be reapplied.   Just a few drops of a blue threadlocker keeps fasteners locked down until the user wants to remove it.

Medium Strength Blue Threadlocker