This Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide is not compatible with a Glock 45 frame. I would recommend using the Gen 5 model slides, which can be found by using the link below:
https://www.opticsplanet.com/zaffiri-precision-rts-glock-19-gen-5-zps-2-rmr-cut-slide.html
Yes, The Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide RMR Cut in Olive Drab should be a close color match to any accessories in ODG (Olive Drab Green).
Yes, the Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide uses a Trijicon RMR optic cut which is compatible with the Holosun 507C which also uses a Trijicon RMR footprint.
Yes, the Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide RMR Cut is compatible with Glock 19 Gen 3 slide internals.
The finish of the Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide RMR Cut might match the grey color of the P80 frame. However, it can't be guaranteed because the actual shade of finish varies between manufactures.
The Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide utilizes an RMR cut. Meaning you can directly attach optics that share the Trijicon RMR footprint including the Trijicon SRO, Holosun 507c, Holosun 508T, Swampfox Liberty, Swampfox Kingslayer, Riton X3 Tactix PRD and many more.
The Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide does not include a channel liner or have one pre-installed.
The Zaffiri Precision RTS Glock 19 Gen 3 ZPS.2 Pistol Slide can work on a Gen 4 Glock 19. However, I would recommend using the Strike Industries Slide Adapter Plate to prevent any movement of the GEN3 recoil rod and spring from possibly damaging your Gen 4 Glock frame. You can find the adapter using the link below:
https://www.opticsplanet.com/strike-industries-slide-adapter-plate-g-sap-for-glock-gen3-to-gen4.html