Safariland holster

[trigga]

Just bought a slightly used 6004-837-121 legdrop holster for cheap. I've researched and have come to like their retaining system. I read that this specific model requires a light to lock in the holster, where does it lock? Im assuming not the trigger guard? Also will any light fit? Didn't give a model light

 

[trigga]

nevermind i was thinking of the als, i got the sls.