US Patent 10393465 3-in-1 mount adapter

A 3-in-1 mount adapter for a firearm having an engagement interface with a plurality of openings includes an attachment base having at least one mounting hole; a mounting plate including at least one ridge receiving through hole aligned with the mounting hole; and at least one fastener assembly including a nut having a ridge passed through the ridge receiving through hole and the openings of said firearm, and a bolt having a threaded portion engaged with the nut and screwed in the mounting hole for affixing the attachment base with the mounting plate; wherein the nut includes a nut head radially extended from the ridge and having an cross sectional area larger than an area of the mounting hole to block the nut head on the mounting plate.