The Walther PDP from T4E : Training 4 Engagement, is an optic ready handgun in a paintball, rubberball, powder ball configuration. Remove the cover plate and use the included OR plates to match your chosen red dot, like the Trijicon SRO in this video, and mount it directly the pistol. If you have a holster that accepts the PDP with an optic it should fit it. This how to video shows the simple steps it takes to add the dot sight to the slide of the PDP. If you lose the plates Umarex offers them as an accessory item that work both on paintball markers and airsoft guns.
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