Firmly secures covers to prevent escapes. Spring steel snaps free for easy user access, and installs in seconds. Assured security for valuable reptiles; a pet wouldn’t think of escaping with Fresh Air™ Screen Clips on the job!Each clip firmly secures a corner of the screen to the terrarium rim without the use of extra hardware or complex installation. Simply slip the top of the clip into the top molding of the cover, then snap the clip’s bottom between the glass and the terrarium frame. Press down and pull out to free the clip and open the lid.Each package contains 1 pair of clips (2 clips).