Pneu Dart Rear Site Screw is only for 190B and 179B pistols, 178B and 176B rifles. A parts list and picture is included in the owner's manual of the rifles and pistols. Rear Site sold separate.
Manual for 176B, 178B, 179B, 190B: https://heritageanimalhealth.com/cataloguploads/PD-manual.pdf
Manual for X-Caliber Rifle: https://heritageanimalhealth.com/cataloguploads/PD-X-Caliber-Manual.pdf
Parts for 178B Air Rifle: https://heritageanimalhealth.com/cataloguploads/PD-Parts-178B.pdf
Parts for 190B Air Pistol: https://heritageanimalhealth.com/cataloguploads/PD-Parts-190B.pdf
Parts for 176B Co2 Rifle: https://heritageanimalhealth.com/cataloguploads/PD-Parts-176B.pdf
Parts for 179B Co2 Pistol: https://heritageanimalhealth.com/cataloguploads/PD-Parts-179B.pdf