Glock models 17 19 20 21 22 23 34 35 40 41 45 47 etc.
NOT FIT all Non-MOS model
A mount is the part that holds a sight to the gun. The PA04 fits into the rear sight dovetail on a non-MOS Glock and gives an Infitac Fast Mini a base to bolt to, since those slides have no optic cut of their own.
On a non-MOS Glock, yes. The PA04 lets you mount an Infitac Fast Mini thermal sight without milling the slide. Check that your model is on the list above first, since the 43X, 48 and MOS pistols aren't covered.