Mount plate is CNC milled from 6AL4V Titanium billet, which has vastly superior mechanical properties to 6061-T6 Aluminum. This kit includes everything you need to mount the 507K/407K/EPS Carry on your PDP 1.0 slide. Not Fit PDP 2.0. Since PDP 1.0 has no recoil lug, this adapter plate is designed to tight fit on the slide, sometimes needing to press it in. Adding a little oil or removing a little coating will make it easier. Compatible with Walther PDP 1.0 and Holosun 407K/507K/EPS Carry. Compatible with Holosun 407K/507K/EPS Carry Not guaranteed to fit other reflex sights. Please note that it is not compatible with 407C/507C NOT FIT PDP 2.0 Thickness: .095" thick Material: 6AL4V (Grade 5)Titanium. Lengthen Posts for the maximum thread engagement, Ultra Low Profile