These Are Awesome - After years of research and development there is finally a .22 L.R. conversion kit on the market for the 7.62x39 caliber AK-47 rifle. Even better, it is simple to install, easy to put in and take out, and even better ... they work great. These have been extensively tested and are proven to work great in all stamped receiver AK-47 rifles. The manual say's that they are tested with Romanian and Zastava based rifles which is what the Croatian factory had available for testing but the unit if properly installed should work in virtually all stamped receiver AK-47 type rifles.