The LPM - 1H optic mount is an abbreviation for the following: Low Profile Mount - 1st model, heavy duty. CSA manufactured this mount to just barely clear the receiver cover so as to create a nice cheek weld on the stock. Due to this optimal check weld, iron sights cannot be used while the mount is attached to the side rail. This mount is manufactured from high quality aluminum alloy and has been hardcoat anodized for added surface strength, abrasion resistance, and corrosion protection.The picatinny rail is centered over the receiver cover and is positioned away from ejected shell casings. This mount should only be used with optics that will not extend into the path of ejected casings - such as red dot optics. If an optic is used that extends beyond the picatinny rail, there is a high probability that the optic will be impacted regularly by ejected casings.