This disclosure describes embodiments of an ambidextrous or reversible safety mechanism for firearms. The safety mechanism can be utilized on specific rifles and shotguns, for example an AK47, SAIGA or similar firearms, as a retrofit to reposition the existing safety mechanism to a configuration similar to or nearly identical to an AR15, M16 or similar firearms. In this way, personnel familiar with the safety operation of the AR15 or M16 will be able to operate the retrofit firearm without learning the operation of a new mechanism. Once retrofitted, the firearm safety mechanism will have the same visual appearance, action, and “feel” as the firearm with which they are familiar. The distance from the grip (trigger) to the engagement portion of the safety mechanism of the retrofit firearm will be very similar to that of the familiar firearm.