Just in case you were wondering, the Gen 5 Glock 19 and 17 have 1913 sized rail holes, and not standard Glock holes. Meaning a key for a Glock sized hole will fit the rail and may rattle around, but a standard milspec 1913 sized attachment will work perfectly. I tested both the Streamlight TLR2GHL
and Surefire X300u
and the 1913 keys fit perfectly.
and Surefire X300u and the 1913 keys fit perfectly.