It's really not needed as the striker is never cocked except when the trigger is pulled, plus it has a firing pin safety in case it's dropped & also has a trigger bar safety shelf in the trigger housing that prevents the bar from going down unless the trigger is pulled ... There are some out there but wouldn't waste my time & you'll have to modify the frame to install it.
You're kidding, right! Whatever you do DO NOT LISTEN to this advice. It is completely incorrect! Sounds like the author has been reading way too many Glock advertisements!
Look, first of all, UNLESS THE TRIGGER IS PULLED, every Glock striker is under CONSTANT 75 (+) percent tension.
Second, the performance and reliability of the striker safety is largely dependent upon the integrity and performance of the TRIGGER SAFETY. (Some of you guys must remember the federal governments's HUD Glock safety tests, right! You know, the government safety tests that Glock pistols FAILED!)
Third, Glock pistols' so-called 'drop safety' is NO DROP SAFETY AT ALL; or, at least, NOT in the historical sense of the term. That shelf the wings of the trigger bar ride in is, in reality, an anti-binding mechanism. It's sole purpose is to prevent the trigger bar's 'sear kick-plate' from becoming lodged behind the striker lug when the pistol is dropped.
Rather than preventing a Glock from firing this so-called 'drop safety' actually allows a Glock pistol to CONTINUE TO FIRE after it has taken a hard fall.
THERE IS ONLY ONE PRINCIPAL SAFETY MECHANISM ON EVERY FACTORY-STANDARD GLOCK PISTOL. IT IS THE LEVER ON EVERY GLOCK'S TRIGGER-FACE. WITHOUT THAT LEVER BEING KEPT IN PERFECT WORKING ORDER, A GLOCK PISTOL IS COMPLETELY UNSAFE TO USE. PERIOD, NO IF'S, NO AND'S, NO BUT'S!
Wow, somebody really 'DRANK THE KOOL-AID' on this one! Internet gun forum palaver and misleading advertising information at its worst! 🙃