I wanted to mount a Vortex Defender XL to my Zev slide with the 4-40 posts. I had searched everywhere and it seemed the only way would be to grind off the posts or buy a new slide. Then I stumbled upon this plate. Was able to mount with no problem, just had to use the screws that came with the XL as the ones supplied with plate were too long. No fault of SAS, they’re for a DPP. It sits a little high but it’s for a competition gun not conceal carry. Super happy with the plate!