L2D does not mention a cap being included.
The OpticsPlanet Exclusive L2D Combat Precision Match Fluted/Threaded Barrel will be compatible with the Shadow Systems MR920.
Around 3.8oz with thread protector and o-ring.
The L2D Combat Precision Match Fluted/Threaded Barrel might work with a PSA Dagger since it is a Glock 19 clone. However, I recommend contacting PSA to confirm compatibility of Glock 19 aftermarket barrels with the PSA Dagger.
Yes, the L2D Combat Precision Match Fluted/Threaded Barrel, Glock 19 will fit a Glock 19X as well as a Glock 45.
The manufacturer doesn't specify if the L2D Combat Precision Match Fluted/Threaded Barrels can accept +P ammunition. I recommend contacting the manufacturer in regards to that information.
Yes. The L2D Combat Precision Match Fluted/Threaded Barrel will work for a 19x. It is also compatible with Glock 19's gen 2-5.
The L2D Combat Precision Match G19 Threaded Barrels are compatible with Glock 19 Gen 3, Gen4, Gen 5 firearms ( Including Glock 19X ), as long as the Wolf Freedom slide is same size there should be no issues.
Yes, the thread protector with matching finish is included.
I have linked a threaded barrel below for the Glock 34.
https://www.opticsplanet.com/trybe-defense-glock-34-match-grade-threaded-pistol-barrel.html?_iv_code=TRB-PTB-GLCK-TPBG34-DLC