Ameriglo TCAP sights correctly.
The TCAP differs from the ordinary CAP sight in having a thinner front blade (0.125" versus 0.140") that allows more daylight on either side of the front in the rear notch and doesn't obscure quite as much of the target. This allows for more precision and plenty of speed.
Naturally, they appear to have been discontinued. I'm tempted to buy a couple more sets to replace the standard CAPs on my Glocks that have them.
The gun functioned without drama and the front sight didn't fly off, so I reckon we're all good.
This makes 1,200 rounds fired since the gun was cleaned or lubricated with no malfunctions. 800 rounds to go.