Norsso P365XL Rail Slide Black. 125 in 3.7 in Width: 1 in Height: 1.375 in Fabric/Material: Stainless Steel Features of Norsso P365XL Rail Slide Optic mount thread pitch: M4 x 0.7 Cosmetic/Lighting Porting Package Contents: Norsso P365XL Rail Slide What firearm models does the manufacturer say Norsso P365XL Rail Slide is compatible with? The manufacturer says that Norsso P365XL Rail Slide is compatible with SIG Sauer P365 XLNorsso N365XL-RAIL-507K-BLK: P365XL Rail Slide Black