holosun and threaded fits gen 5 3 4 fits all 19 size slides 26,19,19x,45,19c basically the most common it's a ballistic advantage threaded barrel didn't come with a cover so i bought one but cost me 160 w/o taxes new has abt 150 rounds thru it in pretty decent shape asking 70 and and holosun has some wear down but works just fine no box has screw and have a universal mount if you have a non mos will remove your back sights and put the plate then you can mount what ever optic asking 130 for holosun and 210 for everything basically selling a kit to max out your glock send serious offers also have a 9mm kris's vec mag willing to sell for the right price