It's called a slide lock..
Bunkered down in the war room somewhere in the high desert of southern Idaho where I discuss all things firearms and self defense training... call us text us 620-794-6223 email us [email protected] like us on FB and check out our web page patriotdefense13.com the podcast is on iTunes...spotify and stitcher.. Help support the podcast…Check out and join our Patreon for only $5 a month.. https://www.patreon.com/patriotdefense?fan_landing=true